Synthesis, crystal structure, magnetic properties and second harmonic generation of a new noncentrosymmetric coordination compound: Triaqua(4-amino-6-methoxypyrimidine) cuprate(II)sulfate

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) Å, V = 1139.81(7) Å3 and Z = 4. The Cu(II) cation is five-coordinated, 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 OH⋯O, OH⋯S, CH⋯O and NH⋯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 one-dimensional antiferromagnetic character. The magnetic parameters were g = 2.11 and 2J/kB = −36 K.

The Cu(II) cation is five-coordinated by two nitrogen atoms of the 4-amino-6-methoxypyrimidine ligand and three water oxygen atoms. The ligand molecules and the 5-connected Cu centers link each other to give a 1-D corrugated hybrid chain running along the b-axis direction.Figure optionsDownload as PowerPoint slide