Copper(II) 3 ,4, [Cu2(3,4,5-(CH3O)3C6H2CO2)4 (CH3OH)2]·2DMF, was prepared and characterized by elemental analysis, infrared and UV-vis spectra and temperature dependence of magnetic susceptibilities (4.5-300 K). The crystal structure was determined by the single-crystal X-ray diffraction method. It crystallizes in the triclinic space group P 1 _ with a = 8.2110 (13) Å, b = 13.181(2) Å, c = 13.409(2) Å, α = 97.967(3)°, β = 102.378(3)°, γ = 105.009(3)°, V = 1339.8(4) Å 3 , Dx = 1.465 g/cm 3 , and Z = 1. The R1 [I > 2σ(I)] and wR2 (all data) values are 0.0363 and 0.0816, respectively, for all 5991 independent reflections. The crystal contains crystallographically centrosymmetric dinuclear molecule with axial methanol molecules and crystal DMF molecules [Cu···Cu 2.6190(6) Å]. Magnetic susceptibility data show a considerable antiferromagnetic interaction between the two copper(II) ions (2J = -292 cm -1 ). Gas-adsorption behavior was investigated for N2.

Copper(II) complexes with 2,3,4-trimethoxybenzoic acid (H234-tmbz) and 2,4,6-trimethoxybenzoic acid (H246-tmbz), [Cu2(234-tmbz)4(H2O)2] (6) and [Cu(246-tmbz)2(µ-H2O)2(H2O)2]n (7), were synthesized and characterized by elemental analysis, infrared and UV-vis spectra and temperature dependence of magnetic susceptibilities (1.9–300 K). The X-ray crystal structures revealed that the former 6 is a dinuclear cluster having syn-syn-bridged Cu2(µ-234-tmbz)4 core with Cu···Cu separation of 2.6009(7) Å, while the latter 7 is a µ-aqua-bridged chain molecule consisting of Cu(246-tmb)2(µ-H2O)2(H2O)2 units with Cu···Cu separation of 4.1420(5) Å. Temperature dependence of magnetic susceptibilities showed that an antiferromagnetic interaction with 2J = −272 cm−1 for 6 and a weak antiferromagnetic interaction with J = −0.21 cm−1 for 7, between the two copper(II) ions. The adsorption isotherm of 6 showed Types I behavior having a 125.4 m2g−1 of specific surface area.

A new type of X-ray spectrometer and detector system for performing extended X-ray absorption fine structure measurements in the laboratory has been developed. The spectrometer is equipped with an asymmetrically-cut flat crystal monochromator in the magnifying mode and converts the energy dispersion to position dispersion using a position-sensitive detector. Two advantages of this apparatus are that it has no moving parts and that it makes the X-ray path shorter. The application of the spectrometer to amorphous GeSe semiconductors is also presented to show its usefulness.

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