The work presented in this thesis concerns the production of high-temperature spectroscopic line lists for the SO2 and SO3 molecules, for the purposes of astrophysical, terrestrial and industrial applications. Both line lists are computed using ab initio computational methods to calculate rovibrational energy levels and dipole moment transition intensities. The hot SO2 line list is computed usi...

the vo(iv) complexes of tridentate ono schiff base ligands derived from 2- aminobenzoicacid and salicylaldehyde derivatives were synthesized and characterized by ir, uv–vis and elemental analysis. electrochemical properties of the vanadyl complexes were investigated by cyclic voltammetry. a good linear correlation was observed between the oxidation potentials and the electron-withdrawing charac...

nbo analysis and density functional theory (dft: b3lyp/6-311+g**) based method were used to study the impacts of the anomeric effects (ae) on the conformational properties of 2-methoxy-1,2,4,5-tetrahydro-benzo[d]oxepine (1), -thiepine (2) and -selenepine (3). the gibbs free energy difference (geq–gax) values (i.e. δgeq-ax) at 298.15 k and 1 atm between the axial and equatorial conformations inc...

the hydrogen abstraction reaction by oh radical from ch2brch2br (r1) and ch₃chbr2 (r2) is investigated theoretically by semi-classical transition state theory. the stationary points for both reactions are located by using ωb97x-d and kmlyp density functional methods along with cc-pvtz basis. single-point energy calculations are performed at the qcisd(t) and ccsd(t) levels of theory with differe...

α-amylase has been studied extensively from various sides. this enzyme is used in many industries .many applications of this enzyme have encouraged us for greater attempts on the study of α-amylase and to search for more effective processes. in this investigation, the structure of nanotube - catalytic site of bacillus subtilis α- amylase was optimized by hyperchem 7.0 and then it was investigat...

more recently medical chemistry research has been focused on proteins that drive and controlcell cycle progression. among them, the cyclin dependent kinases (cdk’s) are a group ofserine/threonine kinases, which rule the transition between successive stages of the cell cycle. theactivity of cdk’s is regulated by multiple mechanisms, including binding to cyclins, which is a broadclass of positive...

the insertion of an olefinic c=c bond into a metal-carbon bond is of potential interest as a preparativeroute to new products and as results of c-c coupling reactions to organic compounds. the allyl compoundsof mg, react with an olefin by inversion of the allyl group via a six center transition state. these precyclicreactions may be one of the most important classes of organic reactions. the re...

We present an ab initio direct Ehrenfest dynamics scheme using a three time-step integrator. The three different time steps are implemented with nuclear velocity Verlet, nuclear-position-coupled midpoint Fock integrator, and time-dependent Hartree-Fock with a modified midpoint and unitary transformation algorithm. The computational cost of the ab initio direct Ehrenfest dynamics presented here ...

in this work, theoretical investigations on carbon nanotube with oxygen atom have been carried out by firstprinciplescalculations and density functional theory and hartree fock theory in 3-216 and 6-316 basis sets. theinteraction energy of the oxygen atom to a cnt is calculated. the effects of this substitutions have beeninvestigated on the during transplantation (10,0) single-walled carbon nan...

for better understanding of conformational stability of the dipeptide model hco—gly—l—leu—nh2,ab initio and dft computations at hf/6-31g(4 6-311++g(d,p) and b3lyp/6-31g(d) levels oftheory were carried out. geometry optimization of the dipeptide within the leucine (leu) side chainangles (x2 ,x2) resulted in three stable conformations as followings: anti-anti, the most stable one,(xi = 180°, x2 =...