TY - JOUR
T1 - Theoretical studies on the structures and properties of energetic complexes
T2 - cobalt, nickel and copper carbohydrazide nitrates
AU - Huang, Huisheng
AU - Zhang, Tonglai
AU - Zhang, Jianguo
AU - Wang, Liqiong
AU - Yang, Li
AU - Qiao, Xiaojing
AU - Shang, Jing
PY - 2010/2/28
Y1 - 2010/2/28
N2 - The molecular geometries, electronic structures, infrared spectra and thermochemical properties of cobalt and nickel tris(carbohydrazide) nitrates ([Co(CHZ)3] (NO3)2 and [Ni(CHZ)3] (NO3)2) as well as copper bis(carbohydrazide) nitrate ([Cu(CHZ)2 (NO3)2]) were investigated by using the density functional theory. The obtained results show that these three complexes have a six-coordinated octahedron feature, and the nitrate ions are also coordinated with the copper cation. Detailed natural bond orbital (NBO) analyses indicate that the donor-acceptor interactions between the ligands and metal cations result in decreasing of occupancies of amino N-H bond orbitals, and subsequently, cause the stretching vibrations of amino groups to shift to lower wave number, which is in accord with the experimental result. The NBO analyses also show that all of the metal cations are almost in +1 oxidation state, and the M-N coordination bonds are covalent, but the Cu-O coordination bonds are predominantly ionic in nature. The calculated heats of reaction reveal that the synthesis reactions for the studied compounds are exothermic. Moreover, the computed heats of formation predict that the stabilities of the title compounds decrease in the order: [Ni(CHZ)3] (NO3)2≤[Co(CHZ)3] (NO3)2≤[Cu(CHZ)2 (NO3)2], which is in good agreement with the available experimental thermal stabilities.
AB - The molecular geometries, electronic structures, infrared spectra and thermochemical properties of cobalt and nickel tris(carbohydrazide) nitrates ([Co(CHZ)3] (NO3)2 and [Ni(CHZ)3] (NO3)2) as well as copper bis(carbohydrazide) nitrate ([Cu(CHZ)2 (NO3)2]) were investigated by using the density functional theory. The obtained results show that these three complexes have a six-coordinated octahedron feature, and the nitrate ions are also coordinated with the copper cation. Detailed natural bond orbital (NBO) analyses indicate that the donor-acceptor interactions between the ligands and metal cations result in decreasing of occupancies of amino N-H bond orbitals, and subsequently, cause the stretching vibrations of amino groups to shift to lower wave number, which is in accord with the experimental result. The NBO analyses also show that all of the metal cations are almost in +1 oxidation state, and the M-N coordination bonds are covalent, but the Cu-O coordination bonds are predominantly ionic in nature. The calculated heats of reaction reveal that the synthesis reactions for the studied compounds are exothermic. Moreover, the computed heats of formation predict that the stabilities of the title compounds decrease in the order: [Ni(CHZ)3] (NO3)2≤[Co(CHZ)3] (NO3)2≤[Cu(CHZ)2 (NO3)2], which is in good agreement with the available experimental thermal stabilities.
KW - Carbohydrazide
KW - Coordination compound
KW - Density functional theory
KW - Electronic structure
KW - Thermochemical property
UR - http://www.scopus.com/inward/record.url?scp=84055164803&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:84055164803
SN - 0567-7351
VL - 68
SP - 289
EP - 293
JO - Acta Chimica Sinica
JF - Acta Chimica Sinica
IS - 4
ER -