Synthesis, crystal structure, magnetic properties and second harmonic generation of a new noncentrosymmetric coordination compound：Triaqua（4-amino-6-methoxypyrimidine） cuprate（II）sulfate
摘要
The chemical preparation, crystal structure and infrared spectroscopic characterization of the triaqua（4-amino-6-methoxypyrimidine） cuprate（II） sulfate, [Cu（C5H7N3）（H2O）3]SO4, is reported. The compound crystallizes in the noncentrosymmetric orthorhombic space group P212121 with lattice parameters a = 7.9025（3）, b = 11.1189（4）, c = 12.9720（4） , V = 1139.81（7） 3 and Z = 4. The Cu（II） cation is fivecoordinated, in an early half-way between square pyramidal and trigonal bipyramidal fashion, by two nitrogen atoms of the 4-amino-6-methoxypyrimidine ligand and three water oxygen atoms. In the atomic arrangement, the organic ligands and the 5-connected Cu centers are linked with each other to give a 1-D corrugated hybrid chain running along the b-axis direction. The chains are interconnected by the SO42- anions via O–H...O, O–H...S, C–H...O and N–H...O hydrogen bonds to form layers spreading parallel to the（011） plane. The vibrational absorption bands were identified by infrared spectroscopy. Quantitative measurements of the second harmonic generation（SHG） of a powdered sample at 1064 nm were performed and a relative efficiency of 5.2 times the KDP standard was observed. Magnetic properties were also defined to characterize the complex. Magnetic measurements revealed that this material had a onedimensional antiferromagnetic character. The magnetic parameters were g = 2.11 and 2J/k B = -36 K.