The vibrational frequencies for the fundamental modes and the energies of low lying states of alanine in neutral and its zwitterionic form in gas phase have been calculated at RMP2 ab-initio level. The results so obtained have been compared with earlier theoretical calculations and experimental observations of IR and RAMAN spectrum. In the present study, it has been observed that our results ar...

In this study the relationship between choosing appropriate descriptors by genetic algorithm to the Polarizability (POL), Molar Refractivity (MR) and Octanol/water Partition Coefficient (LogP) of barbiturates is studied. The chemical structures of the molecules were optimized using ab initio 6-31G basis set method and Polak-Ribiere algorithm with conjugated gradient within HyperChem 8.0 environ...

the influence of cation-π interactions on the strength and nature of intramolecular o...h hydrogen bond has been investigated by quantum chemical calculations in orthohydroxy benzaldehyde (hba) compound. ab initio calculations have been performed at mp2/6-311++g** level of theory. vibrational frequencies and physical properties such as chemical potential and chemical hardness of these compounds...

to determine the non-bonded interaction energies between naphthalene and b12n12 nano ring in different orientations and distances, geometry of molecules with b3lyp method and 6-31g* basis set optimized. also reactivity and stability of naphthalene alone and in the presence b12n12 nano ring checked. then calculated the nbo, nmr, freq, nics and muliken charge of naphthalene atoms alone and in the...

ab initio calculations at hf/6-31g* level of theory for geometry optimization and mp2/6-31g*//hf/6-31g* for a single point total energy calculation are reported for the importantenergy-minimum conformations and transition-state geometries of 1, 3-diazacyclohepta-1, 2-diene (2) and 1, 3-diazacycloocta-1, 2-diene (3). the c2 symmetric twist-chair (2-tc)conformation of 2 is calculated to be 7.4 kj...

We describe the implementation of a separable pseudopotential into the dual space approach for ab initio density-functional calculations using Gaussian basis functions. We apply this Gaussian dual space method ~GDS/DFT! to the study of II-VI semiconductors ~II5Zn, Cd, Hg; VI5S, Se, Te, Po!. The results compare well with experimental data and demonstrate the general transferability of the separa...

Predicting and characterizing the crystal structure of materials is a key problem in materials research and development. We report the results of ab initio LDA/GGA computations for the following systems: AgAu, AgCd, AgMg, AgMo∗, AgNa, AgNb∗, AgPd, AgRh∗, AgRu∗, AgTc∗, AgTi, AgY, AgZr, AlSc, AuCd, AuMo∗, AuNb, AuPd, AuPt∗, AuRh∗, AuRu∗, AuSc, AuTc∗, AuTi, AuY, AuZr, CdMo∗, CdNb∗, CdPd, CdPt, CdR...