2.On Improvement of Accuracy of the Total Energy Calculated by DV-Xα SCC Method and Its Application to Calculate the MolecularGeometry and Vibrational Force Constants
3.In this work,a full optimal calculation on the moleculargeometry and electronic structure of C24H30O8 has been performed using density functional theory(DFT) methods at B3LYP/6-31G* level.
4.Firstly, the moleculargeometry, electronic structure, IR spectra and thermodynamic properties of octahydro4,3,5,7-tetranitro-l,3,5,7-tetrazocine (HMX) are obtained using density functional theory (DFT) method at B3LYP 76-3 1 1++ G * * lever.
5.Density functional theory(DFT) and ab initio method have been employed to op timize the moleculargeometry of (1,2-μ_2-H)(1,2-μ_2-L)Os_3(CO)_ 10 (L: Cl, Br, I)at B3LYP/CEP-4G, B3LYP/LanL2DZ, RHF/CEP-4G and RHF/La nL2DZ levels, respectively.
6.Geometry optimization and natural bond orbital analyses for Re2(edt)4 were carried out with B3LYP method. Molecular orbitals and excited states for Re2(edt)4 were calculated with single excitation configuration interactions (CIS) method.