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Indexed by:Journal Papers

Date of Publication:2019-07-07

Journal:DALTON TRANSACTIONS

Included Journals:SCIE、EI

Volume:48

Issue:25

Page Number:9243-9249

ISSN No.:1477-9226

Abstract:Three one-dimensional looped coordination polymers with the formula of [Fe(dpds)(2){C(CN)(3)}(2)]dpds (1, dpds = 4,4 '-dipyridyl disulfide), [Fe(dpds)(2)(NCBH3)(2)] (2) and [Fe(dpds)(2)(NCSe)(2)]3.5H(2)O (3) have been synthesized and characterized by single-crystal X-ray crystallography, Mossbauer spectroscopy and magnetic measurements. The spin-crossover (SCO) behaviors of these compounds depend significantly on axial ligands: compound 1 exhibited thermal-induced complete one-step SCO behavior with a T-1/2 of 170 K, and 2 showed incomplete SCO behavior with T-1/2 being 130 K, whereas 3 was paramagnetic. Meanwhile, both compounds 1 and 2 displayed light-induced excited spin-state trapping (LIESST) effects, featuring T-LIESST values of 45 K and 61 K for 1 and 2, respectively, which were independent of exciting laser wavelengths. These results suggest that anions such as C(CN)(3)(-) and NCBH3- with much stronger ligand fields are needed in order to realize spin-state switching, if a ligand such as dpds is adopted to synthesize SCO compounds.