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Characteristics of the ring and linear structures of the boron cluster B and its doped clusters were investigated with DFT/B3LYP/6-31G. The results illustrate that the ring B structure is the most stable configuration compared with other rings. Odd and even linear structures have different bonding; there is one different bond in the center of even linear structures, while the remaining bonds have left and right symmetry. The B cluster upholds the configuration rule of pure ring and linear molecules. However, the N-doped BN cluster exhibits obvious distortion compared with the B molecule. The impurity N changes the structure of the energy band of the B cluster. The wavelength of absorption spectra and electronic circular dichroism of the N-doped BN cluster shifts to a longer wavelength compared with that of the B cluster. [ABSTRACT FROM AUTHOR]

The aim of this research is to determine B cluster of prevalence of personality disorders among high school female students. Statistical Population consists of all female students from first to third grade of high school in five regions in Isfahan. Sample size was 1400 students chosen randomly among 75 schools. Millon multiaxial clinical questionnaire was used as the instrument for data collection. In the final analysis the prevalence rate of antisocial personality disorder signs 0.08%, narcisstic 1.9%, histrionic 6.4% , and borderline 0.08% were specified. These findings belonged to students whose grades were 85 and above and have serious personality disorder signs. But students whose grades were between 74- 85, Providing they had suitable conditions, they were more likely to suffer from personality disorder. The rate of personality disorder prevalence among this group appeared to be as follows: antisocial 1.15% , narcisstic 1.3%, histrionic 14.7% , and borderline 1.9%

Adsorption of CO, N, HO, O, H and NO molecules on B cluster was studied using density functional theory (DFT) with B3LYP functional and 6-311 + G(d,p) basis set. Energies, enthalpies and Gibbs free energies of the adsorption processes were calculated. The thermodynamic data showed that the B cluster is a good adsorbent only for CO, O and NO molecules. The calculated energies of adsorption of N, HO and H on the B cluster were positive values. CO molecule is adsorbed via the carbon atom more effectively, while the nitrogen atom of NO is adsorbed better than the oxygen atom. Also, when NO and O are adsorbed synchronously via both atoms, they dissociate. The edge boron atoms of the B cluster showed more reactivity than the inner atoms. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Density functional theory at the B3LYP/6-311++G(d,p) level was used to study the adsorption and dissociation property of a single H molecule on MgB ( n = 2-7) clusters. The hydrogenated structures with lowest-energy of different cluster sizes demonstrate that H atoms prefer to bind with the terminated B atoms with small coordination number by single bond. The structural and electronic stabilities of the hydrogenated clusters were investigated via analyzing the average binding energy, fragmentation energy, second-order energy difference, vertical ionization potential, vertical electron affinity and HOMO-LUMO gap energy. We also explored the feasibility of hydrogenation on B and MgB clusters from the viewpoints of thermodynamics and kinetics. The results demonstrate that the adsorption and dissociation of H on the MgB clusters vary with cluster sizes. H tends to adsorb on the planar boron clusters rather than on three-dimensional boron clusters. Mg doping on B can improve the H storage both in the terms of thermodynamics and kinetic. Moreover, a new bonding way of H with boron clusters was found. Our work provided valuable information for the future boron-based H storage nano-materials. [ABSTRACT FROM AUTHOR]