The flexibility of long chain substituents influences spin-crossover in isomorphous lipid bilayer crystals.
Iurii GaladzhunRafal KulmaczewskiNamrah ShahidOscar CespedesMark J HowardMalcolm A HalcrowPublished in: Chemical communications (Cambridge, England) (2021)
[Fe(bpp)2][BF4]2 (bpp = 2,6-di{pyrazol-1-yl}pyridine) derivatives with a bent geometry of hexadec-1-ynyl or hexadecyl pyrazole substituents are isomorphous, and high-spin at room temperature. However, only the latter compound undergoes an abrupt, stepwise spin-transition on cooling. This may reflect the different conformational flexibilities of their long chain substituents.