title: All-inorganic networks and tetramer based on tin(II)-containing polyoxometalates: tuning structural and spectral properties with lone-pairs.
abstract: Two MOF-like but all-inorganic polyoxometalate-based networks, [Na7X2W18Sn9Cl5O68·(H2O)m]n (1, X = Si, m = 35; 2, X = Ge, m = 41), and the molecular tetramer Na6[{Na(μ-OH2)(OH2)2}6{Sn6(B-SbW9O33)2}2]·50H2O (3) have been prepared and characterized by X-ray diffraction and spectroscopic methods. All three compounds exhibit unique structural features, and networks 1 and 2 incorporate the highest nuclearity of Sn(II)-containing POMs to date. Tetramer 3 comprises bridging Sn(II) ions with [B-SbW9O33](9-) units and exhibits two highly unusual features, a long-range Sb···Sb interaction and an intramolecular charge-transfer transition involving donation of the lone-pair electron density on both Sb(III) and Sn(II) to the POM. The electronic structure and excited-state dynamics have been studied by transient spectroscopy, spectroelectrochemistry, DFT calculations, and resonance Raman spectroscopy. The synergistic effect of two types of stereoactive lone-pairs on Sb(III) and Sn(II) is critical for the charge-transfer absorption feature in the visible.
authors: Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University , Atlanta, Georgia 30322, United States.
authors: Chongchao
authors: C
authors: Zhao
authors: Elliot N
authors: EN
authors: Glass
authors: Bryant
authors: B
authors: Chica
authors: Djamaladdin G
authors: DG
authors: Musaev
authors: Jordan M
authors: JM
authors: Sumliner
authors: R Brian
authors: RB
authors: Dyer
authors: Tianquan
authors: T
authors: Lian
authors: Craig L
authors: CL
authors: Hill
mesh_terms: D000965:Antimony / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D004579:Electron Transport; D008956:Models, Chemical; D013059:Spectrum Analysis, Raman; D017971:Tin Compounds / Q000737:chemistry*; D017973:Tungsten Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D000099294:Polyoxometalates
chemical_list: D000965:Antimony; D017971:Tin Compounds; D017973:Tungsten Compounds; C102296:polyoxometalate I; D000099294:Polyoxometalates