Spin transition triggered by desorption of crystal solvents for a two-dimensional cobalt(<scp>ii</scp>) complex with hydrogen bonding

Designing a new two-dimensional molecular layout by hydrogen bonding.

Hydrogen bonding properties of non-polar solvents.

A combination of high-throughput NMR titration experiments, UV-Vis absorption titrations and data collected from the literature on 1:1 H-bonded complexes has been used to characterise the H-bond properties of non-polar organic solvents: alkanes, perfluorocarbons, aromatic and halogenated organic solvents. The results are analysed in the context of the electrostatic solvent competition model, wh...

Spin transition induced by crystal – liquid crystal transition

Cobalt(II) compounds [Co(C10C8C2-terpy)2](BF4)2 (1) and [Co(C12C10C2terpy)2](BF4)2 (2) (CxCyCz-terpy = 4’-5’’’-Alkyl-1’’’-alkoxy-2,2’:6’,2’’-terpyridine) with branched alkyl chains, based on a terpyridine frame, were synthesized. The cobalt(II) compounds 1 and 2 exhibit the spin transition between low-spin and high-spin with thermal hysteresis loop at the liquid crystal transition temperature (...

Spin Transfer through Hydrogen Bonding

A polarised-neutron diffraction experiment on [Co(NH3)5(H20)][Cr(CN)6] shows the unexpected features of spin populat ions on the cobalt ((0.5(2) e) and the "ammine" hydrogen (0.8(1) e in total) atoms. A local density approximation DV-Xa calculation on a unit that models the molecular geometry in the crystal returns features that are broadly in agreement with the experiment. The calculation also...

Topological transition in a two-dimensional model of liquid crystal.

Simulations of nematic-isotropic transition of liquid crystals in two dimensions are performed using an O2 vector model characterized by nonlinear nearest neighbor spin interaction governed by the fourth Legendre polynomial P4. The system is studied through standard finite-size scaling and conformal rescaling of density profiles of correlation functions. A topological transition between a param...