Surface-induced spin state locking of the [Fe(H2B(pz)2)2(bipy)] spin crossover complex

Temperature- and coverage-dependent studies of the Au(1 1 1)-supported spin crossover Fe(II) complex (SCO) of the type [Fe(H2B(pz)2)2(bipy)] with a suite of surface-sensitive spectroscopy and microscopy tools show that the substrate inhibits thermally induced transitions of the molecular spin state, so that both high-spin and low-spin states are preserved far beyond the spin transition temperature of free molecules. Scanning tunneling microscopy confirms that [Fe(H2B(pz)2)2(bipy)] grows as ordered, molecular bilayer islands at sub-monolayer coverage and as disordered film at higher coverage. The temperature dependence of the electronic structure suggest that the SCO films exhibit a mixture of spin states at room temperature, but upon cooling below the spin crossover transition the film spin state is best described as a mix of high-spin and low-spin state molecules of a ratio that is constant. This locking of the spin state is most likely the result of a substrate-induced conformational change of the interfacial molecules, but it is estimated that also the intra-atomic electron-electron Coulomb correlation energy, or Hubbard correlation energy U, could be an additional contributing factor.

Kagome-like lattice of π–π stacked 3-hydroxyphenalenone on Cu(111)

Three-dimensional arrangement of 3-HPLN on a 2D surface, involving π–π stacking and perpendicular molecule attachment, results in a Kagome lattice.

A rare cause of heart failure--primary hypoparathyroidism

We report a patient who presented with congestive heart failure (ejection fraction 24.4%) and who had previous history of convulsions. Our investigations found him to be a case of primary hypoparathyroidism. He showed a dramatic response with the addition of calcium infusion therapy with almost full recovery of left ventricular function (67% ejection fraction after 16 days of the initial echo). We conclude that in a young patient a thorough investigation for heart failure is never complete without looking for endocrine and metabolic causes. The prognosis in these cases is much better, identification and treatment of the same will yield dramatic results.