Results 271 to 280 of about 170,778 (310)
Some of the next articles are maybe not open access.
1999
In fields such as materials science, electronics, mechanical engineering and bioscience, not to mention physics and chemistry, the keywords “first principles” and “ab initio” have been widely used recently. The principal idea of these keywords is to regard many-atom systems as many-body systems composed of electrons and nuclei, and to treat everything ...
Kaoru Ohno +2 more
openaire +1 more source
In fields such as materials science, electronics, mechanical engineering and bioscience, not to mention physics and chemistry, the keywords “first principles” and “ab initio” have been widely used recently. The principal idea of these keywords is to regard many-atom systems as many-body systems composed of electrons and nuclei, and to treat everything ...
Kaoru Ohno +2 more
openaire +1 more source
2014
?????????????????????? ???????????????????????????????????? ???????????????????????????? ????????, ?????????????????????????? ?????????????????????????? ?????????????????????? ???????????????? ????????????. ???????????????????? ?????????????????????????????? ???????????????? ?????????????? ???????????????? ???????????? ?????????????????? ???????????????
openaire +3 more sources
?????????????????????? ???????????????????????????????????? ???????????????????????????? ????????, ?????????????????????????? ?????????????????????????? ?????????????????????? ???????????????? ????????????. ???????????????????? ?????????????????????????????? ???????????????? ?????????????? ???????????????? ???????????? ?????????????????? ???????????????
openaire +3 more sources
Ab-Initio Potential Functions for Crystals and Ab-Initio Crystal Orbitals
1988To be able to predict crystal densities even for completely hypothetical compounds is of interest. While there are empirical methods to predict crystal densities, these methods depend only on the number and type of fragments or groups. These empirical methods are incapable of predicting differences in crystal densities between various position isomers ...
openaire +1 more source
2019
Ab initio quantum-chemical calculations were performed to investigate the interconversion barriers for the most stable glycine and ??-alanine conformers. The calculations were carried out at the HF and MP2 levels of the theory with the double split valence basis set augmented with polarisation and diffuse shells on all atoms (6???3I++G**).
openaire +1 more source
Ab initio quantum-chemical calculations were performed to investigate the interconversion barriers for the most stable glycine and ??-alanine conformers. The calculations were carried out at the HF and MP2 levels of the theory with the double split valence basis set augmented with polarisation and diffuse shells on all atoms (6???3I++G**).
openaire +1 more source
1998
Various difficulties of classical physics, including inadequate description of atoms and molecules, led to new ways of visualizing physical realities, ways which are embodied in the methods of quantum mechanics. Quantum mechanics is based on the description of particle motion by a wave function, satisfying the Schrodinger equation, which in its “time ...
openaire +1 more source
Various difficulties of classical physics, including inadequate description of atoms and molecules, led to new ways of visualizing physical realities, ways which are embodied in the methods of quantum mechanics. Quantum mechanics is based on the description of particle motion by a wave function, satisfying the Schrodinger equation, which in its “time ...
openaire +1 more source
2016
Both the electronic spectrum of the edge dislocation in crystalline Si and the electronic spectrum of supercell with 64 Si atoms and one oxygen atom in the interstitial position are calculated, using the density functional theory within the generalized gradient approximation.
openaire +1 more source
Both the electronic spectrum of the edge dislocation in crystalline Si and the electronic spectrum of supercell with 64 Si atoms and one oxygen atom in the interstitial position are calculated, using the density functional theory within the generalized gradient approximation.
openaire +1 more source