tetrahedrane is most strained and the smallest cage compound. it attracts organic chemists because ofits unusual bonding nature and highly symmetrical structure. however, many efforts to isolate theparent tetrahedrane have been unsuccessful because of the high reactivity and very short lifetimecaused by the strain in this molecule. modeling of molecules for determination of structuralproperties...

in this paper, we used quantum chemical approach to shed light on the catalytic mechanism of γ-carbonic anhydrase (γ-ca) to convert carbon dioxide to bicarbonate ion. density functional theory (dft) using b3lyp and ub3lyp functional and three split-valance including 6-31g*, 6-311g** and 6-311++g** basis sets were used to calculate the details of electronic structure and electronic energy of act...

for analyzing of compositions molecular orbitals in this article in order to combination only- xylometazolin-c7 x2 (xy) and c60– xylometozolin-c65-x2 (fxy), first got energies of highest occupied molecular orbital (homo) and lowest unoccupied molecular orbital (lumo) by using nbo analyze in gaussian 03 software. then, occupancy parameter, gap of energy, and δnmax were calculated   by support of...

palladium (ii) coordination complexes catalyze the reaction of alcohols with ketones to yield ethers. during the catalytic cycle, the alcohol adds selectively to the β-carbon (anti-markovnikov). in this work, mechanism and kinetics for the reaction of methanol with methyl vinyl ketone (mvk), being catalyzed by pd, has been theoretically investigated in detail. using quantum mechanical approach,...

We investigate helium interactions with lithium using density functional theory. Like other body-centered cubic (bcc) metals, the lowest-energy site for interstitial is a tetrahedral site. However, in shows higher substitutional formation energy than either or octahedral energies, which unique. The calculated migration energies of are also very low (∼ 1 meV), an order magnitude lower those bcc ...

Due to use of different parametric models for establishing species sensitivity distributions (SSDs), comparison of water quality criteria (WQC) for metals of the same group or period in the periodic table is uncertain and results can be biased. To address this inadequacy, a new probabilistic model, based on non-parametric kernel density estimation was developed and optimal bandwidths and testin...