[1] The elastic constants of post-perovskite of chemical composition Mg0.9375Fe0.0625SiO3 and Mg0.8750Fe0.1250SiO3 have been calculated at 0 K and 136 GPa using ab initio methods. For both compositions studied, iron remains in a high-spin state below 180 GPa at 0 K. The effect of spin state on elastic properties is small. Logarithmic derivations of isotropic wave velocities and density with res...

The enormous developments of computer technologies allow the broad employment of ab initioMO theory in foldamer research. In this review, we demonstrate the efficiency and reliability of ab initioMO methods for the description of the helix formation in oligomers of w-amino acids on the basis of representative examples. Thus, ab initio MO theory successfully accompanies foldamer research by conf...

in this paper, the hydrogen bonding (hb) effects on the nmr chemical shifts of selected atoms in serineand serine-nh2o complexes (from one to ten water molecules) have been investigated with quantummechanical calculations of the 15n and 13c tensors. interaction with water molecules causes importantchanges in geometry and electronic structure of serine.for the compound studied, the most importan...

topological indices are the numerical value associated with chemical constitution purporting for correlation ofchemical structure with various physical properties, chemical reactivity or biological activity. graph theory is adelightful playground for the exploration of proof techniques in discrete mathematics and its results haveapplications in many areas of sciences. one of the useful indices ...

topological indices are one of the oldest and most widely used descriptors in quantitative structureproperties relationvhips (qspr). amongst the topological indices used a,s descriptors in qspic., the wienerindex is by far the most popular index. as it has been shown that the wiener index has a strong correlationwith the chemical propenies of the compound.in this study, the relationship between...

Ab initio calculations are performed for the X̃2E′′ 1 and à 2A′′ 2 states of the cyclopentadienyl radical. An important goal of these calculations is to guide the analysis of the experimentally observed Ã2A′′ 2 -X̃ 2E′′ 1 electronic spectrum. Vibrational frequencies for both the X̃ and à state are reported. Large changes