We present an ab initio study on the structural and electronic distortions of modified graphene by creation of vacancies, inclusion of boron atoms, and the coexistence of both, by means of thermodynamics and band structure calculations. In the case of coexistence of boron atoms and vacancy, the modified graphene presents spin polarization only when B atoms locate far from vacancy. Thus, when a boron atom fills single-and di-vacancies, it suppresses the spin polarization of the charge density. In particular when B atoms fill a

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The enthalpy of formation of several species intervening in the atmospheric chemistry of sulfur compounds (SH, H2S, SO, HSO, SOH) have been calculated using density functional theory with correlation consistent basis sets and extrapolation to the complete basis set limit. Excellent agreement with experiment is found for the species of which the enthalpy of formation are well determined. The values predicted for HSO [ΔfH°298K(HSO)=−27.8±2.1 kJ/mol] and SOH [ΔfH°298K(SOH)=−6.8±2.1 kJ/mol] agree well with previous multireference configuration interaction (MR‐CI) calculations. Based on these results, it is determined that the reaction of HSO with ozone is endothermic at all temperatures but spontaneous above 220 K because of entropic effects. Both the reactions of dissociation SOH→H+SO and isomerization HSO→SOH are studied in detail, and the transition states located. The results are also in agreement with the much more costly MR‐CI results. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 80: 439–453, 2000

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