title: Direct solvothermal growth, crystal structures, and optical properties of one-dimensional lanthanide selenidoarsenate(v) polymers [Ln(dien)2(micro3-AsSe4)] (Ln = Nd, Sm): the first example of an AsSe4(3-) anion acting as a ligand to a lanthanide complex.
abstract: Two novel lanthanide selenidoarsenates(v) [Ln(dien)2(micro(3)-AsSe(4))] (Ln = Nd 1, Sm 2, dien = diethylenetriamine) were synthesized by the reactions of As(2)O(3) and Se with Nd(2)O(3) or Sm(2)O(3) in dien under solvothermal conditions. 1 and 2 are in the orthorhombic crystal system with Iba2 and Pbca space groups, respectively. The [AsSe(4)](3-) anion acts as a tridentate micro(3)-AsSe(4) ligand to bridge the lanthanide [Ln(dien)2](3+) complexes leading to one-dimensional neutral [Ln(dien)(2)(micro(3)-AsSe(4))](infinity) chains. The chains contact through hydrogen bonding to form network structures. The lanthanide center lies within a nine-coordinated environment involving six N atoms of two dien ligands and three Se atoms of two different tetrahedral [AsSe(4)](3-) anions forming a distorted monocapped square antiprism. The novel coordination polymers [Nd(dien)2(micro(3)-AsSe(4))](infinity) and [Sm(dien)2(micro(3)-AsSe(4))](infinity) are the first examples of solvothermally synthesized selenidoarsenates with [AsSe(4)](3-) anion acting as a ligand in lanthanide complexes. The band gaps of 2.11 eV for 1, and 2.18 eV for 2 have been derived from optical absorption spectra. TG-DSC curves show that two compounds remove coordinated dien ligands in a single step.
authors.affiliation: College of Chemistry and Chemical Engineering, Suzhou University, Suzhou, 215123, P. R. China. jiadingxian@suda.edu.cn
authors.forename: Dingxian
authors.initials: D
authors.lastname: Jia
authors.forename: Aimei
authors.initials: A
authors.lastname: Zhu
authors.forename: Jie
authors.initials: J
authors.lastname: Deng
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Dai