Ab initio calculations using the UMP2 and UQCISD methods with correlation consistent double-zeta and triple-zeta basis sets were applied to study the reactions of HNO with H and OH radicals. The classical energy barrier for the abstraction H+HNO!H2 +NO is 0.5 kcal/mol. The reaction path of OH+HNO is: OH+HNO!HNO(OH)-complex!TS!NO(H2O)complex!H2O+NO with no energy barrier relative to OH+HNO entra...

This work analyses a case where.Murrell's proposal, stating that a second-order point must lie above a first-order one, is apparently violated. Study at the SCF-UMP2 level within the D95 + + basis set, of one critical point of the O2HFanion, previously proposed to be of order two by Lopez, shows the importance of the electronic correlation. The critical point associated with the 21-1 state shou...

Two major pathways exist in substitution reactions of nucleophiles with allylic substrates (Scheme l).IF3 Attack of the nucleophile at the carbon atom bearing the allylic leaving group leads to direct displacement in a classic sN2 mechanism. Alternatively, attack can also occur at the terminal carbon atom of the allylic double bond, displacing the leaving group in a concerted or consecutive man...

The observation that fourth-order restricted Moller-Plesset perturbation theory (RMP4) gives a satisfactory description of the He:+ potential curve up to the transition structure for dissociation has led to a general examination of the applicability of RMP4 theory to the study of homolytic fragmentation in dications. It appears that, in many cases, RMP4 energies do indeed provide a useful estim...

The first representatives of the radical anions of silatranes XSi(OCH2CH2)3N – organic derivatives of the pentacoordinate silicon atom (X = Ph, 1; p-NO2PhO, 2a; m-NO2PhO, 2b; o-NO2PhO, 2c) – were obtained and characterized by EPR spectroscopy. The structure of 1(−˙), 2a(−˙), 2b(−˙), and 2c(−˙) in polar solvents (C-PCM and COSMO models) was studied at the UMP2 and UB3PW91 levels of theory. The v...

We study the reaction of atomic hydrogen with formic acid and characterize the radical products using IR spectroscopy in a Kr matrix and quantum chemical calculations. The reaction first leads to the formation of an intermediate radical trans-H2COOH, which converts to the more stable radical trans-cis-HC(OH)2via hydrogen atom tunneling on a timescale of hours at 4.3 K. These open-shell species ...

The analytic energy gradients in combined second order Møller-Plesset perturbation theory and conductorlike polarizable continuum model calculations are derived and implemented for spin-restricted closed shell (RMP2), Z-averaged spin-restricted open shell (ZAPT2), and spin-unrestricted open shell (UMP2) cases. Using these methods, the geometries of the S(0) ground state and the T(1) state of th...

This study aims to analyze the effect of labor, UMP and PAD on GRDP per capita. The components used in this include PAD. method research is explanatory uses panel data regression analysis with cross section for 10 provinces time series 11 years. results indicate that Manpower, simultaneously affect capita Sumatera 2010-2020. Labor variable has a positive significant coefficient value 4.531552 s...