Essential oils that contain large concentrations of germacrene D are typically accompanied by cadinane sesquiterpenoids. The acid-catalyzed cyclization of germacrene D to give cadinane and selinane sesquiterpenes has been computationally investigated using both density functional (B3LYP/6-31G(*)) and post Hartree-Fock (MP2/6-31G(* *)) ab initio methods. The calculated energies are in general ag...

A series of oxonium and carboxonium ions and their corresponding protonated dications were investigated by ab initio/IGLO/GIAO-MP2 methods. The calculated 17O and 13C NMR chemical shifts were compared with the solution phase experimental data for the monocations. The structures and energies of a number of oxonium and carboxonium dications and the effect of diprotonation on the 17O and 13C NMR c...

Electronic structure calculations demonstrate poor scaling behavior for large systems. Expensive correction procedures are often necessary to obtain good results, and many of these methods, such as MP2, scale as poorly as O(N^5). With such large problems, proper exploitation of parallelism is essential to make the computation tractable. Therefore, in this class, I want to obtain a fundamental u...

In this study, types of the intermolecular interactions, interaction energies, void analysis diaquabis(3,4-dimethoxybenzoate)bis(nicotinamide)zinc(II) dihydrate (Complex 1), diaquabis(3,4-dimethoxybenzoate)bis(nicotinamide)nickel(II) 2), diaquabis(3,4-dimethoxybenzoate)bis(nicotinamide)cobalt(II) 3), whose crystal structures were characterized before, investigated with help CrystalExplorer prog...

We have performed periodic density functional and periodic local MP2 calculations for the adsorption of hydrogen fluoride and water on the four low index surfaces (001), (100), (101) and (110) of magnesium fluoride. While the adsorption of HF is described well using B3LYP, MP2 is required for a good description of the adsorption of H2O. Post-optimization dispersion corrections of B3LYP are foun...

We discuss the present status and reliability of theoretical predictions of noble-gas hydride molecules. It is shown that the single-reference MP2 calculations can produce a rather inaccurate energy diagram for the formation of noble-gas hydrides, and this may mislead the theoretical predictions. We suggest that the computational dissociation energy of the HY precursors should always be compare...

This paper presents MarkPledge3 (MP3), the most efficient specification of the MarkPledge (MP) technique. The MP technique allows the voter to verify that her vote is correctly encrypted with a soundness of 1−2−α, with 20 ≤ α ≤ 30, just by performing a match of a small string (4-5 characters). Due to its simplicity, verifying the election public data (vote encryptions and tally) in MP3 is 2.6 t...

For selected firstand second-row atoms, correlation-optimized Gaussian k functions have been determined and used in the construction of septuple-z basis sets for the correlation-consistent cc-pVXZ and aug-cc-pVXZ series. Restricted Hartree–Fock ~RHF! and second-order Møller– Plesset ~MP2! total and pair energies were computed for H, N, O, F, S, H2 , N2 , HF, H2O, and (H2O)2 to demonstrate the c...

First-principles calculations were carried out to investigate the torsional potential energy surface (PES) of the secbutyl radical. All the wave function methods employed predict a cis-like stable conformation with a dihedral angle of about 47° in addition to the trans-like global minimum conformation and a gauche conformation. However, most of the popular density functional approaches predict ...