Dysprosium Coordination Polymer Incorporating Dianthracene: Thermo‐induced Phase Transition Accompanied with Magnetic and Optical Changes
Jing‐Cui Liu, Qian Zou, Xin‐Da Huang, Song‐Song Bao, Li‐Min Zheng
Abstract
Abstract Dianthracene ligands obtained through photocycloaddition reaction can undergo de‐dimerization upon heating. Here we report the first examples of lanthanide‐dianthracene coordination polymers with chain structures, namely, [LnL(depma 2 )]Br ⋅ xH 2 O [ 1‐Ln , Ln=Dy (x=5), Gd (x=4); H 2 L= N 1 , N 3 ‐bis(salicylideneimino)diethylenetriamine, depma 2 =photodimerized 9‐diethylphosphonomethylanthracene]. The lanthanide ions possess pseudo‐ D 5h geometries with five equatorial positions occupied by three N and two O atoms from L 2− and two axial positions by the phosphonate oxygen atoms from bridging depma 2 ligands. Thermo‐induced structural transformation is observed for both compounds between 120 and 140 °C, which involves de‐dimerization of depma 2 and elimination of bromoethane. The structural transformation is accompanied with the switch‐on of photoluminescence and, in the case of 1‐Dy , also changes of magnetic dynamics.