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The optical band positions (or crystal field energy levels) of manganese (IV) ions in trigonal barium titanium hexafluoride and barium silicon hexafluoride crystals are computed from the full diagonalization (of energy matrix) method founded on the two-spin-orbit-parameter model which consists of the effects from both the spin-orbit parameters of dn ion and ligand ions. The computed results are in rational agreement with the experimental values. It is found that the large difference of first excited state splitting ΔE (2E) between the manganese (IV)-doped barium titanium hexafluoride and barium silicon hexafluoride crystals is owing mainly to the great difference of trigonal distortion between the fluorine octahedral clusters in the two host crystals. [ABSTRACT FROM AUTHOR]

In this article, the calculations with the high-order perturbation formulas founded on the two-spin-orbit-parameter (of d n ion and that of ligand) model are performed for the spin-Hamiltonian parameters (zero-field splitting D and g factors g // , g ⊥ ) of the tetragonal Co 2+ tetrahedral centers in Y 3 Al 5 O 12 and Y 3 Ga 5 O 12 crystals. The calculated results by using only one adjustable parameter are comparable with the experimental values. The impurity-caused angular distortions in the Co 2+ centers in both crystals are also evaluated. The results are discussed. [ABSTRACT FROM AUTHOR]

A unified calculation of optical band positions and electron paramagnetic resonance (EPR) (or spin-Hamiltonian) parameters for the trigonal Cr3+–Li+centre in CsMgCl3crystal is made by using the complete diagonalisation (of energy matrix) method based on the two-spin–orbit-parameter model. In this model, the contributions from the spin–orbit parameter of central dnion and that of ligand ion are included. From the calculation, the 11 observed optical and EPR data (eight optical band positions and three EPR parametersg//,g⊥,D) are reasonably explained with five adjustable parameters and the defect structure of the Cr3+–Li+centre (which is consistent with the expectation based on the electrostatic interaction) in CsMgCl3is acquired. The results are discussed. [ABSTRACT FROM PUBLISHER]

With different transition metal (TM) complexes as structure directing agents or building units, three new multinary chalcognidometalates based on T3 supertetrahedral nanocluster of [Mn2Ga4Sn4S20]8− have been solvothermally synthesized and structurally characterized. In compound Mn2Ga4Sn4S20[Mn2(en)5]2·4H2O (1, en = ethylenediamine), the neighboring [Mn2Ga4Sn4S20]8− cores were bridged by two pairs of [Mn2(en)5]4+ complex cations via Mn–S bonds to form one-dimensional (1D) neutral chains. Compound Mn2Ga4Sn4S20[Mn(dien)2]4·2H2O (2, dien = diethylenetriamine) contained discrete [Mn2Ga4Sn4S20]8− cores separated by [Mn(dien)2]2+ cations. In compound Mn2Ga4Sn4S20[Mn(teta)]4 (3, teta = triethylenetetramine), each [Mn2Ga4Sn4S20]8− core was covalently attached by four [Mn(teta)]2+ complexes via terminal Mn–S bonds to form a neutral isolated cluster. The photocatalytic experiments indicate that compound 1 was able to degrade rhodamine B (RhB) and crystal violet (CV) under visible irradiation. Furthermore, the luminescence properties and thermal stabilities of the title compounds, as well as the second-order nonlinear optical property of 3 were also studied. [ABSTRACT FROM AUTHOR]

To investigate the effect of the spacers of “V”-type dipyridylamide and dicarboxylic ligands on the structural diversity of Co II coordination polymers, [Co(L 1 )(5-CH 3 -1,3-bdc)]·2H 2 O ( 1 ) [Co(L 2 )(5-CH 3 -1,3-bdc)(H 2 O)]·H 2 O ( 2 ) [Co(L 2 )(5-NO 2 -1,3-bdc)(H 2 O)]·H 2 O ( 3 ) [Co(L 2 )(1,3-bdc)(H 2 O)]·H 2 O ( 4 ) [Co(L 2 )(4,4′-oba)]·3H 2 O ( 5 ) and L 2 ·2H 2 O ( 6 ) [L 1 = N,N′-bis(pyridine-3-yl)pyridine-2,6-dicarboxamide, L 2 = N,N′-bis(pyridine-3-yl)-5-methylisophthalic dicarboxamide, 5-CH 3 -1,3-H 2 bdc = 5-methylisophthalic acid, 5-NO 2 -1,3-H 2 bdc = 5-nitroisophthalic acid, 1,3-H 2 bdc = 1,3-benzenedicarboxylic acid, 4,4′-H 2 oba = 4,4′-oxybis(benzoic acid)] have been hydrothermally synthesized. Complexes 1 – 5 were characterized by IR spectroscopy, thermal analysis, TG and X-ray single-crystal diffraction. Complex 1 is a 2D structure based on (4,4)-connected [Co(5-CH 3 -1,3-bdc)] network and [Co(L 1 )] helixes. Complexes 2 – 4 feature isostructural 2D networks derived from Co-dicarboxylate linear chains and [Co(L 2 )] helixes. Complex 5 show 1D tubular structure constructed by two parrelled [Co(4,4′-oba)] linear chains and [Co(L 2 )] loops. Compound 6 is a 3D supramolecular structure extended by L 2 ligands and water molecules. The effect of the spacers of “V”-type dipyridylamide and dicarboxylic ligands on the structures of the title compounds were discussed. The magnetic property of 1 , the fluorescent behaviors of 1 – 6 and photocatalytic properties of 1 – 5 under UV irradiation were studied. [ABSTRACT FROM AUTHOR]