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Two novel hexa-nickel(II)-substituted Keggin-type {NiPW}-based tungstophosphates [Ni( μ-Tris)(en)( Pr)(damp)(HO)(B- α-PWO)]·10HO ( 1) and [Ni( μ-Tris)(en)(damp)(HO)(B- α-PWO)]·7HO ( 2) (en = ethylenediamine, Pr = CHCHCOO, damp = 2-aminoisobutyrate, Tris = pentaerythritol) were hydrothermally synthesized and characterized by IR spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses, and single-crystal X-ray diffraction. Crystal data for 1: orthorhombic, Pca2, a = 21.6962(7) Å, b = 20.6398(5) Å, c = 14.7825(4) Å, β = 90º, V = 6619.7(3) Å, Z = 4; for 2: orthorhombic, Pca2, a = 21.6978(9) Å, b = 20.6658(7) Å, c = 14.7767(4) Å, β = 90º, V = 6625.9(4) Å, Z = 4. 1 consists of a {Ni( μ-Tris)(en)( Pr)(damp)(HO)} core and a [B- α-PWO] (PW) unit and is covalently functionalized by one Pr and one damp, as well as en and Tris ligands. The structure of 2 is the same to 1 except that the Pr anion in 1 is substituted by the other damp ligand. Most interestingly, 1 contains four kinds of organic ligands, while 2 includes three kinds of organic ligands, which are first observed in polyoxometalate chemistry. [ABSTRACT FROM AUTHOR]

Four new hexa-nickel(II)-substituted Keggin-type tungstophosphates [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·6HO ( 1, oeen = N-(2-hydroxyethyl)enediamine), [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·13HO ( 2), [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·3HO ( 3, tran = 1,4,7-triazonane) and [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·6HO ( 4) have hydrothermally made by controlling their reaction temperatures. 1- 4 have been characterized by elemental analyses, IR spectra, powder X-ray diffraction, thermogravimetric analyses and single-crystal X-ray diffraction, respectively. Structural analyses reveal that they consist of {Ni(μ-OH)(HO)} cores and B-α-PWO (PW) units, and further are stabilized by organic neutral oeen/tran molecules. 1- 3 are isolated clusters while 4 is the 1D chain structure. It should be noted that the tran molecules in 3 and 4 are derived from the oeen molecules in the starting materials. [ABSTRACT FROM AUTHOR]

Abstract: A heteroleptic nickel-bis-1,2-dithiolene ion–pair complex, [BzQl][Ni(dmit)(mnt)] (where BzQl+ =1-(benzyl)quinolinium; dmit2− =2-thioxo-1,3-dithiole-4,5-dithiolate, mnt2− =maleonitriledithiolate), was synthesized and characterized structurally, which exhibited novel magnetic bistability. The compound crystallized in triclinic system with space group P-1. The anions and cations form alternating layered alignments, and the anionic layer is built by the irregularly heteroleptic [Ni(dmit)(mnt)]− chains, where the neighboring anions are connected via lateral-to-lateral S…S contacts of dmit2− ligands. The temperature dependences of magnetic susceptibility follow the S=½ Heisenberg alternating linear-chain model in high-temperature phase and Curie–Weiss law in low-temperature phase. [Copyright &y& Elsevier]

A new heteroleptic nickel-bis-1,2-dithiolene ion-pair complex, (4-ClBz-1-APy)[Ni(dmit)(mnt)] ( 1 ) (where 4-ClBz-1-APy + = p-chloro-benzyliden-1-aminopyridinium; dmit 2− = 2-thioxo-1, 3-dithiole-4, 5-dithiolate; mnt 2− = maleonitriledithiolate) was synthesized and characterized structurally. The IR spectra, thermal analysis, magnetic and near-IR absorption properties have been investigated for 1 . Complex 1 crystallized in monoclinic system with space group P 2 1 . The anions and cations form the mixed stacked columns separated by the cation columns. The anion stacks are irregular, in which two neighboring heteroleptic [Ni(dmit)(mnt)] − anions are separated by one 4-ClBz-1-APy + cation. The neighboring anions are connected via lateral-to-lateral S…S contacts of dmit 2− ligands and short H…N, H…S and C…S contacts are observed between the cations and the anions. Magnetic susceptibility measurement shows that the magnetic data follows the S = 1 / 2 Heisenberg alternating linear-chain model in the temperature range 40–300 K and Curie-Weiss law below 40 K for 1 . Salts 1 exhibits a intense near-IR absorption in the region of 900–1400 nm, and this near-IR absorption feature makes it to be a promising optical material. [ABSTRACT FROM AUTHOR]