Cooperativity in spin crossover materials as ligand's responsibility - investigations of the Fe(ii) - 1,3-bis((1H-tetrazol-1-yl)methyl)bicyclo[1.1.1]pentane system

Christian Knoll; Danny Müller; Marco Seifried; Gerald Giester; Jan M Welch; Werner Artner; Klaudia Hradil; Michael Reissner; Peter Weinberger

doi:10.1039/c8dt00781k

Cooperativity in spin crossover materials as ligand's responsibility - investigations of the Fe(ii) - 1,3-bis((1H-tetrazol-1-yl)methyl)bicyclo[1.1.1]pentane system

Dalton Trans. 2018 Apr 24;47(16):5553-5557. doi: 10.1039/c8dt00781k.

Authors

Christian Knoll¹, Danny Müller, Marco Seifried, Gerald Giester, Jan M Welch, Werner Artner, Klaudia Hradil, Michael Reissner, Peter Weinberger

Affiliation

¹ Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, 1060 Vienna, Austria. danny.mueller@tuwien.ac.at.

PMID: 29623332
DOI: 10.1039/c8dt00781k

Abstract

Criteria for a technologically relevant spin crossover (SCO) material include temperature and abruptness. A series of Fe(ii) - 1,3-bis((1H-tetrazol-1-yl)methyl)bicyclo[1.1.1]pentane SCO complexes with various anions (BF4-, ClO4-, and PF6-) designed using a structure-property based concept is reported. All complexes feature abrupt SCO-behavior with T1/2 between 170 K and 187 K. These materials demonstrate that without stabilizing the effects of incorporated solvents or a hydrogen bond-network, the observed cooperativity during high-spin-low-spin transition is anion independent and originates only from the rigidity and internal strain of the propellane-moiety in the ligand. Spectroscopy and structural investigations of these materials are supported by quantum chemical calculations.