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Experimental and Theoretical Insights on the Structural, Electronic, and Magnetic Properties of the Quaternary Selenides EuPrCuSe 3 and EuNdCuSe 3. Inorg Chem 2024; 63:9040-9049. [PMID: 38710009 PMCID: PMC11110001 DOI: 10.1021/acs.inorgchem.3c04560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 04/02/2024] [Accepted: 04/15/2024] [Indexed: 05/08/2024]
Abstract
Magnetic semiconductors EuPrCuSe3 and EuNdCuSe3 were obtained by using the halide flux method. Their crystal structures and magnetic properties were studied and discussed. Optical properties of the obtained selenides were studied by the means of diffuse reflectance spectroscopy, which revealed the values of 1.92/1.97 and 0.90/0.94 eV for the direct and indirect band gaps of Ln = Nd/Pr, respectively. The structural, electronic, and magnetic properties of the obtained compounds were additionally studied with spin-polarized density functional theory calculations, wherein both systems were found to be two new examples of semiconducting quaternary selenides with disperse conduction bands of Nd/Pr 5d character. The modeling showed that various magnetic orderings in the systems have subtle influences on the alignments/overlaps between the Se/Cu, Eu, and Pr/Nd bands, and that the spin-state energetics are very dependent upon the treatment of electron correlation, but a distinguishing feature in the case of ferromagnetic coupling is that the spin density on the Se atoms is maximized. Overall, the calculations are in good agreement with the experimental characterization of ferromagnetism in the bulk crystals, wherein the ferromagnetic transition occurs at temperatures of about 2.5 K for EuPrCuSe3 and about 3 K for EuNdCuSe3.
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Correction: Anion-driven tetrel bond-induced engineering of lead( ii) architectures with N′-(1-(2-pyridyl)ethylidene)nicotinohydrazide: experimental and theoretical findings. Inorg Chem Front 2022. [DOI: 10.1039/d2qi90035a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Correction for ‘Anion-driven tetrel bond-induced engineering of lead(ii) architectures with N′-(1-(2-pyridyl)ethylidene)nicotinohydrazide: experimental and theoretical findings’ by Ghodrat Mahmoudi et al., Inorg. Chem. Front., 2017, 4, 171–182, https://doi.org/10.1039/C6QI00477F
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Coordination polymers fabricated from Cd(NO 3) 2 and N, N′, O-pincer-type isonicotinoylhydrazone-based polytopic ligands – an insight from experimental and theoretical investigations. CrystEngComm 2022. [DOI: 10.1039/d2ce00294a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three new Cd(ii) coordination polymers based on isonicotinohydrazide ligands (HLI, HLII) differing in the presence of a methyl unit have been obtained and extensively characterized by experimental and computational approaches.
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Solvent-Induced Formation of Novel Ni(II) Complexes Derived from Bis-Thiosemicarbazone Ligand: An Insight from Experimental and Theoretical Investigations. Int J Mol Sci 2021; 22:ijms22105337. [PMID: 34069455 PMCID: PMC8159110 DOI: 10.3390/ijms22105337] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/03/2021] [Accepted: 05/10/2021] [Indexed: 11/16/2022] Open
Abstract
In this work, we report solvent-induced complexation properties of a new N2S2 tetradentate bis-thiosemicarbazone ligand (H2LI), prepared by the condensation of 4-phenylthiosemicarbazide with bis-aldehyde, namely 2,2'-(ethane-1,2-diylbis(oxy)dibenzaldehyde, towards nickel(II). Using ethanol as a reaction medium allowed the isolation of a discrete mononuclear homoleptic complex [NiLI] (1), for which its crystal structure contains three independent molecules, namely 1-I, 1-II, and 1-III, in the asymmetric unit. The doubly deprotonated ligand LI in the structure of 1 is coordinated in a cis-manner through the azomethine nitrogen atoms and the thiocarbonyl sulfur atoms. The coordination geometry around metal centers in all the three crystallographically independent molecules of 1 is best described as the seesaw structure. Interestingly, using methanol as a reaction medium in the same synthesis allowed for the isolation of a discrete mononuclear homoleptic complex [Ni(LII)2] (2), where LII is a monodeprotonated ligand 2-(2-(2-(2-(dimethoxymethyl)phenoxy)ethoxy)benzylidene)-N-phenylhydrazine-1-carbothioamide (HLII). The ligand LII was formed in situ from the reaction of LI with methanol upon coordination to the metal center under synthetic conditions. In the structure of 2, two ligands LII are coordinated in a trans-manner through the azomethine nitrogen atom and the thiocarbonyl sulfur atom, also yielding a seesaw coordination geometry around the metal center. The charge and energy decomposition scheme ETS-NOCV allows for the conclusion that both structures are stabilized by a bunch of London dispersion-driven intermolecular interactions, including predominantly N-H∙∙∙S and N-H∙∙∙O hydrogen bonds in 1 and 2, respectively; they are further augmented by less typical C-H∙∙∙X (where X = S, N, O, π), CH∙∙∙HC, π∙∙∙π stacking and the most striking, attractive long-range intermolecular C-H∙∙∙Ni preagostic interactions. The latter are found to be determined by both stabilizing Coulomb forces and an exchange-correlation contribution as revealed by the IQA energy decomposition scheme. Interestingly, the analogous long-range C-H∙∙∙S interactions are characterized by a repulsive Coulomb contribution and the prevailing attractive exchange-correlation constituent. The electron density of the delocalized bonds (EDDB) method shows that the nickel(II) atom shares only ~0.8|e| due to the σ-conjugation with the adjacent in-plane atoms, demonstrating a very weak σ-metalloaromatic character.
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Supramolecular structures of Ni II and Cu II with the sterically demanding Schiff base dyes driven by cooperative action of preagostic and other non-covalent interactions. IUCRJ 2021; 8:351-361. [PMID: 33953922 PMCID: PMC8086159 DOI: 10.1107/s2052252521000610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
This work reports on synthesis and extensive experimental and theoretical investigations on photophysical, structural and thermal properties of the NiII and CuII discrete mononuclear homoleptic complexes [Ni(L I,II)2] and [Cu(L I,II)2] fabricated from the Schiff base dyes o-HOC6H4-CH=N-cyclo-C6H11 (HL I) and o-HOC10H6-CH=N-cyclo-C6H11 (HL II), containing the sterically crowding cyclo-hexyl units. The six-membered metallocycles adopt a clearly defined envelope conformation in [Ni(L II)2], while they are much more planar in the structures of [Ni(L I)2] and [Cu(L I,II)2]. It has been demonstrated by in-depth bonding analyses based on the ETS-NOCV and Interacting Quantum Atoms energy-decomposition schemes that application of the bulky substituents, containing several C-H groups, has led to the formation of a set of classical and unintuitive intra- and inter-molecular interactions. All together they are responsible for the high stability of [Ni(L I,II)2] and [Cu(L I,II)2]. More specifically, London dispersion dominated intramolecular C-H⋯O, C-H⋯N and C-H⋯H-C hydrogen bonds are recognized and, importantly, the attractive, chiefly the Coulomb driven, preagostic (not repulsive anagostic) C-H⋯Ni/Cu interactions have been discovered despite their relatively long distances (∼2.8-3.1 Å). All the complexes are further stabilized by the extremely efficient intermolecular C-H⋯π(benzene) and C-H⋯π(chelate) interactions, where both the charge-delocalization and London dispersion constituents appear to be crucial for the crystal packing of the obtained complexes. All the complexes were found to be photoluminescent in CH2Cl2, with [Cu(L II)2] exhibiting the most pronounced emission - the time-dependent density-functional-theory computations revealed that it is mostly caused by metal-to-ligand charge-transfer transitions.
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Cover Feature: Resonance Assisted Hydrogen Bonding Phenomenon Unveiled through Both Experiments and Theory: A New Family of Ethyl N‐Salicylideneglycinate Dyes (Chem. Eur. J. 57/2020). Chemistry 2020. [DOI: 10.1002/chem.202002769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Resonance Assisted Hydrogen Bonding Phenomenon Unveiled through Both Experiments and Theory: A New Family of Ethyl N-Salicylideneglycinate Dyes. Chemistry 2020; 26:12987-12995. [PMID: 32428288 DOI: 10.1002/chem.202001551] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/07/2020] [Indexed: 11/06/2022]
Abstract
Extensive experimental and theoretical investigations are reported on the nature of resonance-assisted hydrogen bonding phenomenon (RAHB) and its influence on photophysical properties of the newly designed dyes differing in donor-acceptor properties, namely ethyl N-salicylideneglycinate (1), ethyl N-(5-methoxysalicylidene)glycinate (2), ethyl N-(5-bromosalicylidene)glycinate (3) and ethyl N-(5-nitrosalicylidene)glycinate (4). All compounds are thermochromic in the solid state and they contain a typical intramolecular O-H⋅⋅⋅N hydrogen bond formed between the hydroxyl hydrogen atom and the imine nitrogen atom, yielding the enol form in the solid state. It is unveiled, that the magnitude of RAHB effect fine tunes the strength of the O-H⋅⋅⋅N bonding and accordingly the relative populations of the enol, cis-keto and trans-keto forms leading to variation of the photophysical properties of 1-4. It is determined, that the electron-withdrawing NO2 in 4 amplifies the most RAHB effect causing the breaking of the O-H⋅⋅⋅N hydrogen bond and accordingly formation of the dominant cis-keto isomer in both the solid state and EtOH. To this end, the UV/Vis spectra of 1-3 in EtOH revealed the exclusive presence of the enol form, while the prevalent contribution of the cis-keto form was found for 4. Furthermore, only compound 4 is emissive in the solid state in ambient condition due to dual emission arising from the cis-keto* and trans-keto* forms, while 2 was found to be highly emissive in EtOH. It is revealed qualitatively and quantitatively, based on the ETS-NOCV charge and energy decomposition scheme and the EDDB population-based method, that RAHB is strongly a non-local phenomenon based on electrons pumping or sucking through both the π- and σ-channels, which accordingly exerts chemical bonding changes at both the phenyl ring and predominantly a distant O-H⋅⋅⋅N area.
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Cover Feature: Origin of Hydrocarbons Stability from a Computational Perspective: A Case Study of Ortho‐Xylene Isomers (ChemPhysChem 6/2020). Chemphyschem 2020. [DOI: 10.1002/cphc.202000140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Origin of Hydrocarbons Stability from a Computational Perspective: A Case Study of Ortho-Xylene Isomers. Chemphyschem 2020; 21:494-502. [PMID: 31990431 DOI: 10.1002/cphc.202000066] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Indexed: 01/12/2023]
Abstract
It is shown herein that intuitive and text-book steric-clash based interpretation of the higher energy "in-in" xylene isomer (as arising solely from the repulsive CH⋅⋅⋅HC contact) with respect to the corresponding global-minimum "out-out" configuration (where the clashing C-H bonds are tilted out) is misleading. It is demonstrated that the two hydrogen atoms engaged in the CH⋅⋅⋅HC contact in "in-in" are involved in attractive interaction so they cannot explain the lower stability of this isomer. We have proven, based on the arsenal of modern bonding descriptors (EDDB, HOMA, NICS, FALDI, ETS-NOCV, DAFH, FAMSEC, IQA), that in order to understand the relative stability of "in-in" versus "out-out" xylenes isomers one must consider the changes in the electronic structure encompassing the entire molecules as arising from the cooperative action of hyperconjugation, aromaticity and unintuitive London dispersion plus charge delocalization based intra-molecular CH⋅⋅⋅HC interactions.
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Lead(ii) coordination polymers driven by pyridine-hydrazine donors: from anion-guided self-assembly to structural features. Dalton Trans 2020; 49:11238-11248. [DOI: 10.1039/d0dt01704c] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This work unveils an indispensable role of London dispersion forces and relativistic effects in tetrel and covalent bonds of the type Pb–X (X = O, N, S, I), which drives formation of extended architectures of lead(ii) coordination polymers.
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Substituent Effect on Conformational Preferences in Ground and Excited States of Selected Schiff Bases: An Insight from Theoretical Calculations. J Phys Chem A 2019; 124:63-73. [DOI: 10.1021/acs.jpca.9b10254] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Formation of active species from ruthenium alkylidene catalysts-an insight from computational perspective. J Mol Model 2019; 25:331. [PMID: 31701244 DOI: 10.1007/s00894-019-4202-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 09/03/2019] [Indexed: 10/25/2022]
Abstract
Ruthenium alkylidene complexes are commonly used as olefin metathesis catalysts. Initiation of the catalytic process requires formation of a 14-electron active ruthenium species via dissociation of a respective ligand. In the present work, this initiation step has been computationally studied for the Grubbs-type catalysts (H2IMes)(PCy3)(Cl)2Ru=CHPh, (H2IMes)(PCy3)(Cl)2Ru=CH-CH=CMe2 and (H2IMes)(3-Br-py)2(Cl)2Ru=CHPh, and the Hoveyda-Grubbs-type catalysts (H2IMes)(Cl)2Ru=CH(o-OiPrC6H4), (H2IMes)(Cl)2Ru=CH(5-NO2-2-OiPrC6H3), and (H2IMes)(Cl)2Ru=CH(2-OiPr-3-PhC6H3), using density functional theory (DFT). Additionally, the extended-transition-state combined with the natural orbitals for the chemical valence (ETS-NOCV) and the interacting quantum atoms (IQA) energy decomposition methods were applied. The computationally determined activity order within both families of the catalysts and the activation parameters are in agreement with reported experimental data. The significance of solvent simulation and the basis set superposition error (BSSE) correction is discussed. ETS-NOCV demonstrates that the bond between the dissociating ligand and the Ru-based fragment is largely ionic followed by the charge delocalizations: σ(Ru-P) and π(Ru-P) and the secondary CH…Cl, CH…π, and CH…HC interactions. In the case of transition state structures, the majority of stabilization stems from London dispersion forces exerted by the efficient CH…Cl, CH…π, and CH…HC interactions. Interestingly, the height of the electronic dissociation barriers is, however, directly connected with the prevalent (unfavourable) changes in the electrostatic and orbital interaction contributions despite the favourable relief in Pauli repulsion and geometry reorganization terms during the activation process. According to the IQA results, the isopropoxy group in the Hoveyda-Grubbs-type catalysts is an efficient donor of intra-molecular interactions which are important for the activity of these catalysts.
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Aggregation-Induced Emission-Based Sensing Platform for Selective Detection of Zn 2+ : Experimental and Theoretical Investigations. Chemphyschem 2019; 20:1630-1639. [PMID: 30983076 DOI: 10.1002/cphc.201900113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/08/2019] [Indexed: 12/21/2022]
Abstract
Fluorescent chemosensors with aggregation induced emission enhancement (AIEE) emerge as promising tools in the field of sensing materials. Herein, we report the design, synthesis and applicability of a Schiff base chemosensor 1-(benzo[1,3]dioxol-4-ylmethylene-hydrazonomethyl)-naphthalen-2-ol (Hbdhn) of AIE characteristics that exhibits highly effective and selective response towards Zn2+ . The sensing effect of Hbdhn was evaluated by means of absorption/emission spectra and corresponding underlying photophysical mechanisms were proposed based on extensive quantum-chemical (TD)DFT calculations. The aggregated states in different DMSO/H2 O ratios and in a presence of Zn2+ were examined by fluorescence lifetime measurements, dynamic light scattering and scanning electron microscopy studies. The bioimaging abilities of Hbdhn were evaluated for Zn2+ in HepG2 cancer cells. The results demonstrate instant, stable in time and reproducible, colorimetric turn-on response with superb selectivity and sensitivity of Hbdhn towards Zn2+ , based on chelation enhanced fluorescence mechanism. AIEE improves further Hbdhn properties, leading to strong, long-lived fluorescence, with appearance of rod-like particles, in 90 % of water in DMSO and only 10 % of water in DMSO in the presence of Zn2+ . All these features combined with successful biomaging studies make Hbdhn one of the most promising candidate for practical applications among recently proposed related systems.
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Kinetic and Potential Energy Contributions to a Chemical Bond from the Charge and Energy Decomposition Scheme of Extended Transition State Natural Orbitals for Chemical Valence. J Phys Chem A 2019; 123:4616-4622. [PMID: 31058501 DOI: 10.1021/acs.jpca.9b01420] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This work provides novel physical insight into the nature of a chemical bond by exploring qualitative and quantitative relations between the natural orbitals for chemical valence (NOCV)-based deformation density bonding channels Δρ i ( i = σ, π, δ, etc.) and the corresponding kinetic Δ Ti and potential energy Δ Vi contributions within the charge and energy decomposition scheme ETS-NOCV implemented in the Kohn-Sham-based Amsterdam Density Functional (ADF) package. It is determined that interfragment dative and covalent-type electron charge reorganizations upon formation of a series of strong and weak bonds employing main-group elements are due to lowering of the negative kinetic energy contributions, as opposed to the intrafragment polarizations (e.g., hyperconjugations in ethane), which are, in contrary, driven by the potential energy (electrostatic) component. Complementary, formation of π-contributions in N2 is accompanied by lowering of both kinetic and potential energy constituents. Remarkably, well-known globally stabilizing back-donation (M → ligand, where M is a transition metal) and donation (ligand → M) processes, ubiquitous in organometallic species, have been discovered for the first time to be driven by the opposite Δ Ti/Δ Vi mechanisms, namely, the former contribution is associated with the negative kinetic term (which outweighs the positive potential energy), whereas the latter charge delocalization into electrophilic transition metals leads to an attractive electrostatic stabilization (and positive kinetic energy).
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Chameleon-like Nature of Anagostic Interactions and Its Impact on Metalloaromaticity in Square-Planar Nickel Complexes. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00062] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Correction: Structural versatility of the quasi-aromatic Möbius type zinc( ii)-pseudohalide complexes – experimental and theoretical investigations. RSC Adv 2019; 9:26547. [PMID: 35532404 PMCID: PMC9070569 DOI: 10.1039/c9ra90062d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 08/14/2019] [Indexed: 11/28/2022] Open
Abstract
Correction for ‘Structural versatility of the quasi-aromatic Möbius type zinc(ii)-pseudohalide complexes – experimental and theoretical investigations’ by Mariusz P. Mitoraj et al., RSC Adv., 2019, 9, 23764–23773.
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Structural versatility of the quasi-aromatic Möbius type zinc(ii)-pseudohalide complexes – experimental and theoretical investigations. RSC Adv 2019; 9:23764-23773. [PMID: 35530624 PMCID: PMC9069493 DOI: 10.1039/c9ra05276c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/23/2019] [Accepted: 07/24/2019] [Indexed: 12/03/2022] Open
Abstract
In this contribution we report for the first time fabrication, isolation, structural and theoretical characterization of the quasi-aromatic Möbius complexes [Zn(NCS)2LI] (1), [Zn2(μ1,1-N3)2(LI)2][ZnCl3(MeOH)]2·6MeOH (2) and [Zn(NCS)LII]2[Zn(NCS)4]·MeOH (3), constructed from 1,2-diphenyl-1,2-bis((phenyl(pyridin-2-yl)methylene)hydrazono)ethane (LI) or benzilbis(acetylpyridin-2-yl)methylidenehydrazone (LII), respectively, and ZnCl2 mixed with NH4NCS or NaN3. Structures 1–3 are dictated by both the bulkiness of the organic ligand and the nature of the inorganic counter ion. As evidenced from single crystal X-ray diffraction data species 1 has a neutral discrete heteroleptic mononuclear structure, whereas, complexes 2 and 3 exhibit a salt-like structure. Each structure contains a ZnII atom chelated by one tetradentate twisted ligand LI creating the unusual Möbius type topology. Theoretical investigations based on the EDDB method allowed us to determine that it constitutes the quasi-aromatic Möbius motif where a metal only induces the π-delocalization solely within the ligand part: 2.44|e| in 3, 3.14|e| in 2 and 3.44|e| in 1. It is found, that the degree of quasi-aromatic π-delocalization in the case of zinc species is significantly weaker (by ∼50%) than the corresponding estimations for cadmium systems – it is associated with the Zn–N bonds being more polar than the related Cd–N connections. The ETS-NOCV showed, that the monomers in 1 are bonded primarily through London dispersion forces, whereas long-range electrostatic stabilization is crucial in 2 and 3. A number of non-covalent interactions are additionally identified in the lattices of 1–3. Interplay between various types of non-covalent interactions allowed for isolation of rare examples of Zn(ii) based quasi-aromatic Möbius type species.![]()
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N
-Thiophosphorylthioureas RNHC(S)NHP(S)(Oi
Pr)2
as an Excellent Platform for Studying the Synergy between Hydrogen-Hydrogen Bonding and Other Families of Non-Covalent Interactions. European J Org Chem 2018. [DOI: 10.1002/ejoc.201801041] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Abstract
The cooperative action of multiple non-covalent interactions allowed for the assembly of a new series of PbII coordination compounds.
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Ligand-Driven Coordination Sphere-Induced Engineering of Hybride Materials Constructed from PbCl2 and Bis-Pyridyl Organic Linkers for Single-Component Light-Emitting Phosphors. Inorg Chem 2017; 56:9698-9709. [DOI: 10.1021/acs.inorgchem.7b01189] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Abstract
Nitrones are important building blocks for natural and biologically active compounds, used as spin-trap reagents and therapeutic agents. All this makes nitrones intriguing and valuable compounds for fundamental studies and as useful chemicals in various synthetic strategies. Therefore, nitrones are still of great interest and in the limelight of researches. With our initial goal to solve synthetic problems toward 5-phenyl-2,2'-bipyridine (Phbpy), we found that this reaction can proceed through the formation of 6-phenyl-3-(pyridin-2-yl)-1,2,4-triazin-4(3H)-ol (4-OH), which rapidly isomerizes to a 3,4-dihydro-1,2,4-triazine-based nitrone, namely 6-phenyl-3-pyridin-2-yl-2,3-dihydro-1,2,4-triazin-4-oxide (4'), This encouraged us to study condensation of hydrazonophenylacetaldehyde oxime (2), obtained from 2-isonitrosoacetophenone (1), with other aldehydes. The reaction with both salicylaldehyde and p-tolualdehyde leads to the open-chain isomers, namely (2-hydroxybenzylidene)hydrazono-2-phenylacetaldehyde oxime (5) and (4-methylbenzylidene)hydrazono-2-phenylacetaldehyde oxime (6), respectively. The latter product exists in solution in equilibrium with its cyclic isomer 6-phenyl-3-(4-methylphenyl)-2,3-dihydro-1,2,4-triazin-4-oxide (6'), while the former one exists in solution exclusively in the open-chain form. It was also found that 2 reacts with acetone with the formation of 3,3-dimethyl-6-phenyl-2,3-dihydro-1,2,4-triazin-4-oxide (7'), which also exists in solution in equilibrium with its open-chain isomer 2-phenyl-2-(propan-2-ylidenehydrazono)acetaldehyde oxime (7). The static DFT as well as ab initio molecular dynamics simulations have corroborated the experimental findings.
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Anion-driven tetrel bond-induced engineering of lead(ii) architectures with N′-(1-(2-pyridyl)ethylidene)nicotinohydrazide: experimental and theoretical findings. Inorg Chem Front 2017. [DOI: 10.1039/c6qi00477f] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new series of PbII coordination compounds was assembled with the N′-(1-(2-pyridyl)ethylidene)nicotinohydrazide ligand and various auxiliary inorganic counterions.
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Complexes and salts of the nitrogen-rich triazole–tetrazole hybrid ligand with alkali and alkaline earth metal cations: experimental and theoretical findings. NEW J CHEM 2017. [DOI: 10.1039/c7nj01391d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of the triazole–tetrazole based compounds with Li+, Na+, K+, Mg2+, Ca2+ and Ba2+ was obtained and fully characterised.
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Polar protic solvent-trapping polymorphism of the HgII-hydrazone coordination polymer: experimental and theoretical findings. CrystEngComm 2017. [DOI: 10.1039/c7ce00626h] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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An intermolecular pyrene excimer in the pyrene-labeled N-thiophosphorylated thiourea and its nickel(ii) complex. Inorg Chem Front 2016. [DOI: 10.1039/c6qi00298f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
(1-pyrene)NHC(S)NHP(S)(OiPr)2 (HL) and its NiII complex ([NiL2]) have been synthesized. Both HL and [NiL2] were found to be emissive in solution of CH2Cl2, which is due to the concentration dependent emission of the pyrene monomer and excimer.
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Influence of the Homopolar Dihydrogen Bonding CH⋅⋅⋅HC on Coordination Geometry: Experimental and Theoretical Studies. Chemistry 2015; 21:16679-87. [DOI: 10.1002/chem.201501499] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Indexed: 11/07/2022]
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Luminescent mononuclear mixed ligand complexes of copper(I) with 5-phenyl-2,2'-bipyridine and triphenylphosphine. Dalton Trans 2015; 44:16824-32. [PMID: 26347226 DOI: 10.1039/c5dt02755a] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction of 5-phenyl-2,2'-bipyridine (L) with a mixture of CuI or [Cu(CH3CN)4]BF4 and PPh3 leads to mononuclear heteroleptic complexes [CuL(PPh3)I] (1) and [CuL(PPh3)2]BF4 (2). According to X-ray diffraction, L crystallizes in the monoclinic space group P21/n, exhibiting a disorder over four orientations. Complexes 1 and 2 crystallize in the monoclinic space groups P21/c and P21, respectively. 1 comprises a discrete neutral molecule, while 2 has an ionic structure containing [CuL(PPh3)2](+) and BF4(-). Both structures reveal that each tetracoordinated copper(i) atom is linked to two nitrogen atoms of L, one iodide and one PPh3 in the structure of 1, or two PPh3 in the structure of 2 with the formation of a distorted tetrahedral coordination core. The structure of 2 is additionally stabilized by a weak intramolecular ππ stacking interaction formed between two adjacent phenyl rings of two PPh3 ligands. Hirshfeld surface analysis showed that the structures of both complexes are mainly characterized by HH and CH contacts as well as by IH in the structure of 1 and FH in the structure of 2. The 2D fingerprint plots of two different molecules in the structure of L showed that both molecules exhibit contacts for ππ stacking interactions. The factors important for the stability of 1 and 2 were further quantitatively and qualitatively characterized by the charge and energy decomposition method ETS-NOCV. According to diffuse reflectance spectroscopy in the solid state, free L exhibits bands exclusively in the UV region, while the spectra of 1 and 2 also contain bands in the visible range up to about 500 and 600 nm. All three compounds were found to be emissive in the solid state. DFT calculations have shown that, while emission of L is due to the ligand-centered π→π* transition, luminescence of 1 and 2 was assigned to a (M + X)LCT and MLCT excited states, respectively.
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Metal ion influences distortion of the ligand in the structure of [M{2-MeO(O)CC6H4NHC(S)NP(S)(OiPr)2}2] (M = Zn(II), Cd(II)) complexes: a driving force for intermolecular aggregation. Dalton Trans 2015; 44:14101-9. [PMID: 26172266 DOI: 10.1039/c5dt02189h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction of the in situ deprotonated N-thiophosphorylated thiourea 2-MeO(O)CC6H4NHC(S)NHP(S)(OiPr)2 () with MCl2 (M = Zn(II), Cd(II)) in aqueous ethanol leads to complexes of the formula . Both compounds crystallise in the triclinic space group P1[combining macron] with Z = 2 and the metal cations are found in a tetrahedral S2S coordination environment formed by the C-S and P-S sulfur atoms. The crystal structures reveal intramolecular N-HO[double bond, length as m-dash]C hydrogen bonds formed within the 2-MeO(O)CC6H4NH fragments. Both structures are further stabilised by intermolecular ππ stacking interactions, which are more efficient in . Here, a pronounced dimeric intermolecular aggregate is observed which goes along with a pronounced distortion of the chelate [(S)CNP(S)](-) backbone of the ligand upon coordination to Cd(II) as well as a significantly distorted coordination tetrahedron CdS2S. The aggregation is also reflected in the positive electrospray ionisation (ESI) mass spectrum of the Cd(II) complex, which exhibits peaks for the dimeric cations [Cd2L3](+), [Cd2L4 + H](+) and [Cd2L4 + Na](+), while for the Zn(II) analogue only monomeric species were observed. Quantum chemical ETS-NOCV (ADF) calculations confirm the higher stability of dimers in compared with . The ππ stacking interactions are prodominantly due to dispersion contributions, though the electrostatic and orbital interaction components are also important. QTAIM (ADF) type calculations additionally quantify the covalent and non-covalent interactions in the momomers.
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Ratiometric sensing of lysine through the formation of the pyrene excimer: experimental and computational studies. Chem Commun (Camb) 2015; 51:8536-9. [DOI: 10.1039/c5cc01359c] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lysine assisted ratiometric monomer to excimer conversion of pyrene derivatives allows intracellular lysine detections.
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32
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Modulation of pKa by cyclodextrins; subtle structural changes induce spectacularly different behaviors. RSC Adv 2015. [DOI: 10.1039/c5ra14032c] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Supramolecular acidity tuning: it is shown that minor structural changes of guests and hosts molecules may be of great importance for the complexation-induced pKa shifts and their temperature dependency.
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Abstract
A rhodamine–pyridine conjugate, REDA-2PC, can selectively monitor NCS− in human embryonic kidney cells 293. Visible light excitable probe allows fluorescence and naked eye detection of nanomolar NCS−.
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34
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An anion induced multisignaling probe for Hg2+ and its application for fish kidney and liver tissue imaging studies. Dalton Trans 2015; 44:13186-95. [DOI: 10.1039/c5dt01854d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A highly efficient binder for the selective recognition and determination of Hg(NO3)2 concentration in kidney and liver tissues of fish using a fluorescence method is described.
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35
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Nature of the water/aromatic parallel alignment interactions. J Comput Chem 2014; 36:171-80. [DOI: 10.1002/jcc.23783] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 10/05/2014] [Accepted: 10/17/2014] [Indexed: 11/06/2022]
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36
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Nucleic Acid Quadruplexes Based on 8-Halo-9-deazaxanthines: Energetics and Noncovalent Interactions in Quadruplex Stems. J Chem Theory Comput 2014; 10:5353-65. [DOI: 10.1021/ct5007554] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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37
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Supramolecular Coordination Complexes of theN-Thiophosphorylated 2,5-Dithiobiurea [NHC(S)NHP(S)(OiPr)2]2with ZnIIand CdIIIons - Cation-Induced Dinuclear Mesocate Structure versus Tetranuclear Nanoscaled Aggregate. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402544] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
The internal rotation in ammonia borane (AB) was studied on the basis of natural orbitals for chemical valence (NOCV) and eigenvectors for Pauli repulsion (NOPR). We found that the total hyperconjugation stabilization (ca. 5 kcal mol−1), based on the charge transfer from the occupied σ (B–H) orbitals into the empty σ*(N–H), slightly favors the staggered conformation over the eclipsed one; however, the barrier to internal rotation in ammonia borane can be understood predominantly in a ‘classical’ way, as originating from the steric (Pauli) repulsion contributions (of the kinetic origin) that act solely between N–H and B–H bonds. Repulsion between the lone pair of ammonia and the adjacent B–H bonds was found to be dominant in absolute terms; however, it does not determine the rotational barrier. Similar conclusions on the role of CH↔HC repulsion appeared to be valid for isoelectronic ethane. Pauli (kinetic) repulsion acting between the N-H and B-H bonds of ammonia borane ![]()
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Complexation properties of N-thiophosphorylated thiourea 2-PyNHC(S)NHP(S)(OiPr)2 towards Ni(II). Dalton Trans 2013; 42:5252-7. [PMID: 23474583 DOI: 10.1039/c3dt32886d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Reaction of the deprotonated N-thiophosphorylated thiourea 2-PyNHC(S)NHP(S)(OiPr)2 (HL) with NiCl2 leads to the complex [Ni{2-PyNHC(S)NP(S)(OiPr)2}2] ([NiL2]) with unprecedented 1,5,7-N,N′,S-coordination of the ligand. Recrystallization of [NiL2] from a mixture of CH2Cl2–n-hexane or acetone–n-hexane leads to [Ni(L-1,5,7-N,N′,S)2]·CH2Cl2 and [Ni(L-1,5,7-N,N′,S)2], respectively. The latter complex, in turn, shows a temperature-induced polymorphism. [NiL2] in solution shows a paramagnetic distorted octahedral structure where the metal center is coordinated through the nitrogen atoms of the phosphorylamide and pyridyl group functions, and oxygen atoms of the phosphorylamide unit. Furthermore, in the solid state at low temperature, [Ni(L-1,5,7-N,N′,S)2] is shown from high-frequency EPR measurements to possess an S = 1 ground state with large anisotropy.
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Experimental and theoretical investigations of the NiII complex with N-phosphorylated thiourea iPrNHC(S)NHP(O)(OPh)2. CrystEngComm 2013. [DOI: 10.1039/c3ce41195h] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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A coumarin-based “turn-on” fluorescent sensor for the determination of Al3+: single crystal X-ray structure and cell staining properties. Dalton Trans 2013; 42:10198-207. [DOI: 10.1039/c3dt51045j] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Crucial Influence of the Intramolecular Hydrogen Bond on the Coordination Mode of RC(S)NHP(S)(OiPr)2in Homoleptic Complexes with NiII. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200890] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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43
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Abstract
The ETS-NOCV analysis was applied to describe the σ-hole in a systematic way in a series of halogen compounds, CF3-X (X = I, Br, Cl, F), CH3I, and C(CH3)nH3-n-I (n = 1,2,3), as well as for the example germanium-based systems. GeXH3, X = F, Cl, H. Further, the ETS-NOCV analysis was used to characterize bonding with ammonia for these systems. The results show that the dominating contribution to the deformation density, Δρ 1 , exhibits the negative-value area with a minimum, corresponding to σ-hole. The "size" (spatial extension of negative value) and "depth" (minium value) of the σ-hole varies for different X in CF3-X, and is influenced by the carbon substituents (fluorine atoms, hydrogen atoms, methyl groups). The size and depth of σ-hole decreases in the order: I, Br, Cl, F in CF3-X. In CH3-I and C(CH3)nH3-n-I, compared to CF3-I, introduction of hydrogen atoms and their subsequent replacements by methyl groups lead to the systematic decrease in the σ-hole size and depth. The ETS-NOCV σ-hole picture is consistent with the existence the positive MEP area at the extension of σ-hole generating bond. Finally, the NOCV deformation density contours as well as by the ETS orbital-interaction energy indicate that the σ-hole-based bond with ammonia contains a degree of covalent contribution. In all analyzed systems, it was found that the electrostatic energy is approximately two times larger than the orbital-interaction term, confirming the indisputable role of the electrostatic stabilization in halogen bonding and σ-hole bonding.
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Influence of CH2Cl2for the structure stabilization of the NiIIcomplex [Ni{6-MeO(O)CC6H4NHC(S)NP(S)(OiPr)2-1,5-S,S′}2]·CH2Cl2. CrystEngComm 2012. [DOI: 10.1039/c1ce06322g] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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QTAIM and ETS-NOCV Analyses of Intramolecular CH···HC Interactions in Metal Complexes. J Phys Chem A 2011; 115:12746-57. [DOI: 10.1021/jp203797y] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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46
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Multiple Boron−Boron Bonds in Neutral Molecules: An Insight from the Extended Transition State Method and the Natural Orbitals for Chemical Valence Scheme. Inorg Chem 2011; 50:2168-74. [DOI: 10.1021/ic101576g] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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47
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Solvent-induced 1,3-N,S- vs. 1,5-S,S′-coordination in the NiII complex [Ni{p-Me2NC6H4NHC(S)NP(S)(OiPr)2}2]. CrystEngComm 2011. [DOI: 10.1039/c1ce05387f] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Theoretical analysis of the resonance assisted hydrogen bond based on the combined extended transition state method and natural orbitals for chemical valence scheme. J Phys Chem A 2010; 114:8581-90. [PMID: 20099799 DOI: 10.1021/jp911405e] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have analyzed hydrogen bonding in a number of species, containing from two to four hydrogen bonds. The examples were chosen in such a way that they would enable us to examine three different hydrogen bonds involving OH-O, NH-O, and NH-N. A common feature of the investigated systems is that they all are expected to exhibit resonance assisted hydrogen bonding (RAHB) in the electronic pi-framework. Our analysis was based on a recently developed method that combines the extended transition state scheme with the theory of natural orbitals for chemical valence (ETS-NOCV). We find that hydrogen bonding is associated with charge rearrangement in both the electronic sigma-framework (Deltarho(sigma)) and the electronic pi-framework (Deltarho(pi)). However the stabilization due to Deltarho(sigma) is four times as important as the stabilization (RAHB) due to Deltarho(pi). Stabilization due to the electrostatic interaction (DeltaE(elstat)) between the two monomers that are brought together to form the hydrogen bonds is also important. However DeltaE(el) cannot alone account for the strength of the hydrogen bonds as it is more than compensated for by the repulsive Pauli repulsion (DeltaE(Pauli)). When N' is part of an aromatic ring, N'H-O and N'H-N bonds are similar in strength to OH-O links involving carboxylic groups. However, NH-O bonds involving amide groups (-NH(2)) are considerably weaker than the OH-O links mentioned above. In systems with different hydrogen bonds, their relative strength is determined collectively in such a way as to optimize the total interaction. This can result in that one of the bonds (OH-O, NH-O, and NH-N) becomes particularly strong or exceptionally weak. Even within the same dimer two X'-HX bonds of the same type can show quite different strength.
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σ-Donor and π-Acceptor Properties of Phosphorus Ligands: An Insight from the Natural Orbitals for Chemical Valence. Inorg Chem 2009; 49:578-82. [DOI: 10.1021/ic901736n] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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50
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Theoretical description of bonding in cis-W(CO)4(piperidine)2 and its dimer. J Mol Model 2009; 16:337-42. [DOI: 10.1007/s00894-009-0545-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 06/09/2009] [Indexed: 10/20/2022]
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