High-spin low-spin transition

TL;DR

This study uses temperature-dependent nuclear inelastic-scattering to investigate spin state transitions in a complex, revealing significant changes in iron-ligand bonds associated with spin crossover, supported by theoretical density-functional calculations.

Contribution

It demonstrates the application of NIS combined with DFT simulations to directly observe spin crossover effects in a specific iron complex.

Findings

Increased iron-ligand bond stretching during spin crossover

Correlation between experimental NIS spectra and theoretical models

Confirmation of spin state change through spectroscopic evidence

Abstract

Temperature dependent nuclear inelastic-scattering (NIS) of synchrotron radiation was applied to investigate both spin states of the spin-crossover complex [Fe(tpa)(NCS)(2)] (tpa = tris(2-pyridylmethyl)amine). A remarkable increase of the iron-ligand bond stretching upon spin crossover has unambiguously been identified by comparing the measured NIS spectra with theoretical simulations based on density-functional calculations.