X-ray crystal structure and vibrational spectra of hydrazides and their metal complexes. Part II. Hexaaquacobalt(II)bis(phthalhydrazidato)tetrahydrate

The hexaaquacobalt(II)bis(phthalhydrazidato)tetrahydrate, [Co(H-2)(6)](C8N2O2H5)(2)center dot 4H(2)O is examined using single crystal X-ray diffraction analysis. The crystals are triclinic, space group P (1) over bar, with a = 9.757(1), b = 10.955(2), c = 11.106(1), alpha = 100.79(2), beta = 90.35(3) gamma = 91.54(1) and Z = 2. In [Co(H2O)(6)](C8N2O2H5)(2)center dot 4H(2)O, the cobalt(II) is coordinated by six water ligands and the [Co(H2O)(6)](2+) is associated with the two O-deprotonated phthalhydrazidato ions only by hydrogen bonds. The infrared and Raman spectra of phthalhvdrazide (PH) and infrared spectra of deuterated derivative phthalhydrazide (PD) and of [Co(H2O)(6)](C8N2O2H5)(2)center dot 4H(2)O are reported. The theoretical wavenumbers, infrared intensities and Raman scattering activities have been calculated using density functional (B3LYP) method with the 6-311 ++G(d,p) basis set. The Calculated potential energy distribution has proved to be of great help in assigning the spectra PH, its deuterated derivative and [Co(H2O)(6)](C8N2O2H5)(2)center dot 4H(2)O. The results from natural bond orbital (NBO) analysis for keto-hydroxy form of PH are presented. (c) 2007 Elsevier B.V. All rights reserved.