Infrared spectra of NH2NO, NH2NO+, and NNOH+ and of the N2⋯H2O complex trapped in solid neon

Phosphenic isocyanate (O2PNCO): Gas-phase generation, characterization, and photodecomposition reactions

Phosphenic isocyanate (O2PNCO), a novel phosphorus-containing small molecule has been generated by thermolysis of a dioxaphospholane-based precursor. The characterization of O2PNCO with IR and UV-vis spectroscopy in solid N2 and...

Detection and structural characterization of nitrosamide H2NNO: A central intermediate in deNOx processes

The structure and bonding of H₂NNO, the simplest N-nitrosamine, and a key intermediate in deNO_x processes, have been precisely characterized using a combination of rotational spectroscopy of its more abundant isotopic species and high-level quantum chemical calculations. Isotopic spectroscopy provides compelling evidence that this species is formed promptly in our discharge expansion via the NH₂ + NO reaction and is collisionally cooled prior to subsequent unimolecular rearrangement. H₂NNO is found to possess an essentially planar geometry, an NNO angle of 113.67(5)°, and a N-N bond length of 1.342(3) Å; in combination with the derived nitrogen quadrupole coupling constants, its bonding is best described as an admixture of uncharged dipolar (H₂N-N=O, single bond) and zwitterion (H₂N⁺=N-O^-, double bond) structures. At the CCSD(T) level, and extrapolating to the complete basis set limit, the planar geometry appears to represent the minimum of the potential surface, although the torsional potential of this molecule is extremely flat.

Protonation of N2O and NO2 in a solid phase

Adsorption of gaseous N₂O or NO₂ on the acidic surface Brønsted centers of the strongest known solid acid, H(CHB₁₁F₁₁), results in formation of Brønsted and Lewis cationic superacids, NN–OH⁺ and NN⁺–OH.

Cation dinitrogen complexes [N(2)...X...N(2)]+, X+=H+, Li+, Na+, Be(2+), Mg(2+)

The complexes of dinitrogen with five cations (H(+), Li(+), Na(+), Be(2+) and Mg(2+)) up to four N(2) molecules have been calculated at the MP2/6-311++G(d,p) level. Energetic and geometric aspects have been determined together with absolute shieldings (GIAO). The atoms in molecules methodology has been used to analyze energy, charge and volume of these complexes.

A complete active space self-consistent field study of the photochemistry of nitrosamine

Photodissociation mechanisms of nitrosamine (NH2NO) have been studied at the complete active space self-consistent field level of theory in conjunction with atomic-natural-orbital-type basis sets. In addition, the energies of all the critical points and the potential energy curves connecting them have been recomputed with the multiconfigurational second-order perturbation method. Ground state minimum of nitrosamine has a C1 nonplanar structure with the hydrogen atoms of the amino moiety out of the plane defined by the N-N-O bonds. Electronic transitions to the three lowest states are allowed by selection rules: (i) S0-->S3 (7.41 eV) has an oscillator strength of f=0.0006 and it is assigned as an (npO)0-->(piNO*)2 transition, (ii) S0-->S2 (5.86 eV) has an oscillator strength of f=0.14 and it is assigned as an npN-->piNO* transition, and (iii) S0-->S1 (2.98 eV) has an oscillator strength of f=0.002 and it is assigned as an npO-->piNO* transition. It is found that N-N bond cleavage is the most likely process in all the photochemical relevant states, namely, S1 (1 1A"), S2 (2 1A'), and T1 (1 3A"). While S1 and T1 yield exclusively homolytic dissociation: NH2NO-->NH2 (1 2B1)+NO(X 2Pi), on S2 the latter process constitutes the major path, but two additional minor channels are also available: adiabatic homolytic dissociation: NH2NO-->NH2 (1 2A1)+NO(X 2Pi), and adiabatic oxygen extrusion: NH2NO-->NH2N (1 3A1)+O(3P). The excited species NH2 (1 2A1) experiences a subsequent ultrafast decay to the ground state, the final products in all cases the fragments being in their lowest electronic state. We have not found a unimolecular mechanism connecting excited states with the ground state. In addition, homolytic dissociation in the ground state, tautomerizations to NHNOH and NHNHO, and intersystem crossings to T1 are considered. The most favorable process on this state is the isomerization to NHNOH.