To investigate the ability for spin-state switching of spin-crossover (SCO) complexes adsorbed to solid substrates, the SCO complex [Fe­(H2B­(pz)2)2(phenme4)] (pz = pyrazole, phenme4 = 3,4,7,8-tetramethyl-1,10-phenanthroline) is prepared. The new complex is investigated by magnetic susceptibility measurements and Mößbauer spectroscopy in the solid state and by temperature-dependent UV/vis spectroscopy in a thin film deposited by physical vapor deposition (PVD) on quartz glass. Thermal- and light-induced SCO is observed in the bulk and the film on glass. Submonolayers of this complex obtained by PVD are studied by temperature-dependent near-edge X-ray absorption fine structure (NEXAFS) on Au(111) as well as Bi(111) and by scanning tunneling microscopy (STM) on Au(111). NEXAFS shows thermal- and light-induced spin-state switching of the complex on Bi(111), however, with a large temperature-independent high-spin fraction (∼50%). On the other hand, combined evidence from NEXAFS and STM indicates that on Au(111) the complex dissociates into [Fe­(H2B­(pz)2)2] and phenme4. Similar observations are made with the parent complex [Fe­(H2B­(pz)2)2(phen)], which on Bi(111) stays intact and exhibits thermal-induced as well as light-induced SCO, but on Au(111) dissociates into [Fe­(H2B­(pz)2)2] and phen.

Le Bail and Rietveld analysis of high resolution synchrotron x-ray powder diffraction (SXRPD) data shows unambiguous signatures of the failure of the commensurate 3M modulation model. Using (3 + 1) dimensional superspace group formalism, we have not only confirmed the incommensurate modulation in the premartensite phase with a modulation wavevector of q = 0.337 61(5)c* but also determined the superspace group (Immm(00γ)s00), atomic positions and amplitude of modulations for the incommensurate premartensite phase of Ni2MnGa for the first time. Our results may have important implications in the understanding of the martensitic transition and hence the magnetic field induced strains.

We demonstrate the existence of a charge-density-wave (CDW) associated with an incommensurate periodic lattice distortion on Ni2MnGa surface in the ferromagnetic state. Our temperature dependent photoemission spectra provide compelling evidence of a pseudogap at the Fermi level for TCDW ≤ 270 K that appears at the onset of the pre-martensite phase and persists in the martensite phase. While the width of the pseudogap is about 25 meV, a spectral weight transfer is observed over a much wider energy range that is associated with the CDW.

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A mechanoresponsive, viscochromic, and unsymmetrical azine NDEA probes Al3+ and Cu2+ ions and also co-localizes in the mitochondria of C6 glioma cell lines.