Nuclear inelastic scattering of 1D polymeric Fe(Ⅱ) complexes of 1,2,4-aminotriazole in their high-spin and low-spin state

摘要

The vibrational properties of Fe(II) 1D spin crossover polymers have been characterized by nuclear inelastic scattering (NIS). The complexes under study were the tosylate and perchlorate salts of ([Fe(4-amino-1,2,4-triazole)_3]~(+2))_n complexes. The complexes have LS (S = 0) marker bands in the range of 300–500 cm~(-1), while the marker bands corresponding to the HS (S = 2) state are detected between 200 cm~(-1) and 300 cm~(-1), in line with the decreasing Fe-N bond strengths during the transition from LS to HS. Accompanying DFT calculations using the functional B3LYP and the basis set CEP-31G confirm these assignments.