Unquenched orbital angular momentum in quasi-linear two-coordinate transition metal complexes featuring sterically bulky carbazole ligands†
Abstract
A series of two-coordinate TM compounds, M((tbu)2carb(Ph2CH)2) (M = Mn, Fe, Co; (tbu)2carb(Ph2CH)2 = 1,8-bis(diphenylmethyl)-3,6-ditertbutylcarbazolide). Each of the complexes displays a bent geometry with a N–M–N bond angle ranging from 140.21(10)° to 144.37(15)°. Despite the non-linear geometry, M((tbu)2carb(Ph2CH)2)2 (M = Fe, Co) have substantial spin–orbit coupling, and Co((tbu)2carb(Ph2CH)2)2 displays slow magnetic relaxation with an Ueff value of 30.2 K and a large negative D of −169 cm−1.