A quantum mechanics/molecular mechanics molecular dynamics simulation was performed for liquid water to investigate structural and dynamical properties of this peculiar liquid. The most important region containing a central reference molecule all nearest surrounding molecules (first coordination shell) treated by Hartree-Fock (HF), post-Hartree-Fock [second-order Moller-Plesset perturbation theory (MP2)], hybrid density functional B3LYP [Becke's three parameter (B3) with the correlation Lee,...

Refractive index (RI) measurements, depolarized collision-induced light (CILS) scattering and ab initio quantum chemical calculations are used to determine the dipole (α), dipole–quadrupole (A), dipole–octopole polarizability (E) of adamantane, C10H16. For this molecule symmetry group Td three polarizabilities can be represented by a single scalar quantity. From experiment we obtain for static at T≈400–500 K 107.5±1.1 e2a02Eh−1, higher |A|=102.0±7.8 e2a03Eh−1, |E|=720±80 e2a04Eh−1. We have...

Highly accurate ab initio calculations with specially designed basis sets are reported for Li4. The molecule emerges as a particularly soft system, very anisotropic dipole polarizability and large second hyperpolarizability. An extensive investigation of set electron correlation effects leads to values ᾱ = 387.01 Δα 354.60 e2a02Eh-1. mean hyperpolarizability is γ̄ 2394 × 103 e4a04Eh-3. computational aspects the present effort discussed in view extension quantumchemical studies lithium...

Accurate values have been obtained for the electric dipole (μ) and quadrupole (Θ) moment polarizability (ααβ) of CS, SiO SiS from finite-field many-body perturbation theory coupled cluster calculations. For ground state we μ/ea0 = 0.7903 (CS), −1.1843 (SiO) −0.6124 (SiS) Θ/ea2 0 −1.85 −2.94 −0.37 (SiS). These agree well with available experimental data moment. Discrepancies between experiment are observed SiS. Our best mean isoelectronic CS 28.87 (CS) 29.67 (SiO). is less anisotropic than as...

The dependences of the static dipole polarizabilities per atom (PPAs) on bonding and shape selected stoichiometric aluminum phosphide clusters (ground states higher lying species) small medium sizes have been comprehensively studied at Hartree–Fock second order Møller–Plesset perturbation levels theory. It is shown that nonmonotonic size variations in mean PPAs AlP species which maintain closed cagelike structures, frequently observed clusters, are directly related to covalent homoatomic...

The frequency dependence of the dipole polarizability $\ensuremath{\alpha}(\ensuremath{\omega})$ ${\mathrm{P}}_{4}$ is obtained from refractive index measurements on gaseous phosphorus by means asymmetric white-light interferometry. experimental results in range between 10 000 and 30 300 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ yield an extrapolated static value $\ensuremath{\alpha}{=91.71(92)e}^{2}{a}_{0}^{2}{E}_{H}^{\ensuremath{-}1}.$ An extensive theoretical study, based finite-field...

Abstract A test set of 10 molecules (open and ring forms ozone sulfur dioxide as well water hydrogen sulfide their respective fluoro‐ chloro‐substituted analogs) specific atmospheric interest has been formed to assess the performance various density functional theory methods in (hyper)polarizability calculations against well‐established ab initio methods. The choice these was further based on (i) profound change physics between isomeric systems, e.g., open ( C 2 v ) D 3 h ozone, (ii)...

We have obtained electric properties of P⋮P from finite-field Møller−Plesset perturbation theory, density functional theory and coupled cluster techniques. Reference, near-Hartree−Fock values been with a very large (20s15p10d5f) uncontracted basis set consisting 300 Gaussian-type functions. At the experimental equilibrium bond length Re = 1.8934 Å we obtain self-consistent field 1.0682 ea02 for quadrupole moment (ϑ), −41.68 ea04 hexadecapole (Φ), 51.16 mean ( ) 28.58 e2a02Eh-1 anisotropy...

The synthesis and optoelectronics properties of polyaromatic hydrocarbons (PAHs) doped with boron nitrogen units (BN) monopolize the interest increasing numbers researchers past few years. key concept fueling these attempts lies on prospect engineering novel organic compounds versatile physical chemical using well-known all-carbon systems as scaffolds. Among various BN-doped PAHs synthesized so far, one could distinguish two categories. most common comprises in which BN replace aromatic CC...

We present a rigorous analysis of the performance set twelve DFT methods on calculation static electric polarizability and hyperpolarizability lithium tetramer. Our reveals essential similarities dissimilarities in these methods.

We have obtained accurate static dipole polarizabilities and hyperpolarizabilities for BrCl from finite-field Møller–Plesset perturbation theory coupled cluster calculations. Our best values the properties been at CCSD(T) level of with a large [6s5p5d2f1g/5s4p4d2f1g] basis set are moment μ/ea0 = −0.1778, mean polarizability anisotropy Δα/e2a20Eh−1 20.44, first hyperpolarizability second . At same [6s5p4d1f/5s4p3d1f] set, above vary around experimental bond length Re 2.136 065 Å as

Living communities can be considered as complex systems, and are thus fertile grounds for studies related to statistics dynamics. In this study we revisit the case of rhythmic applause by utilizing model proposed Vázquez et al (2006 Phys. Rev. E 73 036127) augmented with two opposing driving forces, namely desires individuality companionship. To that end, after performing computer simulations a large number oscillators propose an explanation on following open questions: (a) Why does...

We have calculated the static polarizability and hyperpolarizability of ring structure sulphur dioxide. Our best values for mean dipole (ααβ), first (βαβγ) second (γαβγδ) hyperpolarizability, obtained at CCSD(T) level theory with α carefully optimized basis set, are ᾱ=28.94 e2a02Eh−1, β̄=110.6 e3a03Eh−2 γ̄=6117 e4a04Eh−3. At same a set exactly size, relevant quantities open ᾱ=25.84 β̄=30.1 γ̄=3390 e4a04Eh−3 [D. Xenides G. Maroulis, Chem. Phys. Lett. 319, 618 (2000)]. Thus, dioxide is...

We have calculated self-consistent field (SCF) and second-order Møller-Plesset perturbation theory (MP2) for the dihaloethynes X–C≡C–X, X = F, Cl, Br I. All calculations been performed with carefully optimized, flexible basis sets of gaussiantype functions. Our best values quadrupole moment (Θ/ea02) are -0.6524 (FCCF), 3.6612 (ClCCCl), 5.8143 (BrCCBr) 8.3774 (ICCI). The dipole polarizability is strongly anisotropic. For mean (α /e2a02Eh-1) anisotropy (Δα/e2a02Eh-1) we obtain 23.58 15.09...

Accurate values for the dipole polarizability of cyclic form ozone have been obtained from finite-field many-body perturbation theory and coupled-cluster calculations. Our best effort yields near-Hartree - Fock 16.09 mean value anisotropy polarizability. Electron correlation increases by only a few per cent but has stronger effect on . CCSD(T) values, with [9s6p5d1f] basis set, are Thus, is less polarizable than open one which characterized (Maroulis G 1994 J. Chem. Phys. 101 4949).