Our ab initio calculations of the hyperfine parameters for negatively charged vacancy-hydrogen and nitrogen-vacancy-hydrogen complexes in diamond compare static defect models and models which account for the quantum tunneling behavior of hydrogen. The static models give rise to hyperfine splittings that are inconsistent with the experimental electron paramagnetic resonance data. In contrast, th...

in this study the hardness swct was calculated with b3lyp,hf method and 3-21g,6-31g,6-311g basis set .then it was investigated with the best method(b3lyp) and basis set(6-31g) to study the adsorption effects co2 on the hardness of swcnt with gap homo-lumo in two shape: horizontal, vertical and top-center-bridge and we also provide the effects of co2 adsorption on the electronic properties(dos) ...

We have measured hyperfine structure in the first-excited P state (D lines) of all the naturally-occurring alkali atoms. We use high-resolution laser spectroscopy to resolve hyperfine transitions, and measure intervals by locking the frequency shift produced by an acousto-optic modulator to the difference between two transitions. In most cases, the hyperfine coupling constants derived from our ...

J. S. Grossman, L. A. Orozco, M. R. Pearson, J. E. Simsarian,* G. D. Sprouse, and W. Z. Zhao Department of Physics and Astronomy, State University of New York, Stony Brook, New York 11794-3800 (Received 5 April 1999) We have measured the hyperfine structure of the 7P1 2 level for 2082212Fr to a precision of 300 ppm. These measurements along with previous ground state hyperfine structure measure...

Quantum mechanical calculations are performed on 116 conformers of the protein ubiquitin (Lange et al., Science 2008, 320, 1471–1475). The results indicate that the heat of formation (HOF), dipole moment, energy of the frontier orbitals HOMO and LUMO, and HOMO-LUMO gap fluctuate within their corresponding ranges. This study thus provides a link between the conformational dynamics of a protein a...

In the light of computational chemistry, based on morpholinium cation-based Ionic Liquid, their different types of physical, chemical, and biological properties is highlighted. The physical properties are evaluated through the Density Functional Theory (DFT) of Molecular Mechanics and also examine the chemical and biological properties. The difference between Highest Occupied Molecular Orbital ...

UNLABELLED Many chemical concepts hinge on the notion of an orbital called the lowest unoccupied molecular orbital, or LUMO. This hypothetical orbital and the much more concrete highest occupied molecular orbital (HOMO) constitute the two "frontier orbitals", which rationalize a great deal of chemistry. A viable LUMO candidate should have a sensible energy value, a realistic shape with amplitud...

Porphyrins are widely used as dye molecules in solar cells. Knowing the energies of their frontier orbitals is crucial for optimizing the energy level structure of solar cells. We use near edge x-ray absorption fine structure (NEXAFS) spectroscopy to obtain the energy of the lowest unoccupied molecular orbital (LUMO) with respect to the N(1s) core level of the molecule. A systematic energy shif...

High-precision experiments on the ground state hyperfine splitting in highly charged ions performed at the GSI facilities and at the EBITs (see, e.g., Refs. [1, 2, 3]) have triggered intensive theoretical investigations of this effect. The error bars of the theoretical hyperfine splitting values are mainly determined by the nuclear magnetization distribution correction, the so-called Bohr-Weiss...