Using a wide variety of quantum-chemical methods we have analyzed in detail the linear and non-linear optical properties [60]fullerene-chromophore dyads different electron-donor character. The are composed [60]fullerene covalently linked with 2,1,3-benzothiadiazole carbazole derivatives. Linear scaling calculations molecular (hyper)polarizabilities were performed using wave function theory as well density functional (DFT). Within former approach, used both semiempirical (PM3) ab initio...

The electronic and vibrational contributions to the dipole moment, polarizabilities, first hyperpolarizabilities of HArF are reported. These have been computed by using a series systematically built basis sets hierarchy computational methods. has very large hyperpolarizability along z axis. This rationalized invoking difference in structure between ground excited state. argon fluorohydride recently derived characterized. present study provides complementary data for understanding this...

The relationship between nonlinear susceptibilities and hyperpolarizabilities defined using different conventions is reexamined. In previous work [Willetts et al., J. Chem. Phys. 97, 7590 (1992)], relations for microscopic have been derived, but the application of corresponding conversion factors led to several inconsistencies. It shown that macroscopic be taken into account, too, in order arrive at consistently comparable values. complete set are given second harmonic generation, electric...

Macroscopic first-, second-, and third-order susceptibilities of the urea crystal are calculated using static frequency-dependent ab initio molecular (hyper)polarizabilities at self-consistent field (SCF) second-order-Mo/ller–Plesset (MP2) levels. Environmental effects taken into account a rigorous local-field theory compared with anisotropic Lorentz factor approximation. The electric arising from permanent dipoles surrounding molecules is explicitly approach. dipole moment first...

A set of exchange‐correlation functionals, including BLYP, PBE0, B3LYP, BHandHLYP, CAM‐B3LYP, LC‐BLYP, and HSE, has been used to determine static dynamic nonresonant (nuclear relaxation) vibrational (hyper)polarizabilities for a series all‐ trans polymethineimine (PMI) oligomers containing up eight monomer units. These functionals are assessed against reference values obtained using the Møller–Plesset second‐order perturbation theory (MP2) CCSD methods. For smallest oligomer, CCSD(T)...

We designed a series of photochromic derivatives by employing density functional method (CAM-B3LYP/6-31G*). These compounds are based on DAE (diarylethenes), both sides which bonded with benzene and NiBDT (bis(ethylene-1,2-dithiolato)Ni). substituents and, in particular, the moiety known to exhibit very large second hyperpolarizability. The objective this work was develop, DFT methodology, set rules for designing materials presenting following: (i) contrast between physical properties—the...

We synthesized a series of four parent

The electric field poling process of nonlinear optical chromophores embedded in an amorphous polymer matrix was studied using molecular dynamics (MD) simulations. Three systems were considered, consisting a poly(methyl methacrylate) doped with the following chromophores:  N,N-dimethyl-p-nitroaniline (DPNA), 4-(dimethylamino)-4‘-nitrostilbene (DMANS), and N,N‘-di-n-propyl-2,4-dinitro-1,5-diaminobenzene (DPDNDAB). cooling presence simulated at constant NPT conditions annealing. rotational...

The interactions of the antihypertensive AT1 antagonists candesartan and losartan with membrane bilayers were studied through application DSC, Raman, solid state 31P NMR spectroscopies. 1H 13C resonances assigned on basis 1D 2D spectroscopy. A CP broadline fitting methodology in combination ab initio computations was implemented and, conjunction DSC Raman results, provided valuable information regarding perturbation, localization, orientation, dynamic properties drugs models. In particular,...

The potential energy surface (PES) of Ti@C(28) has been revisited, and the stationary points have carefully characterized. In particular, C(2v) symmetry structure considered previously turns out to be a transition state lying 2.3 kcal/mol above ground C(3v) at MP2/6-31G(d) level. A large binding 181.3 is found ROMP2/6-31G(d) Topological analysis generalized density reveals four bond paths between Ti carbon atoms host. character all contacts corresponds partially covalent closed shell...

The large overshoot in (hyper)polarizabilities of quasilinear (1D) chains calculated by applying density functional theory with conventional functionals is investigated for several 2D and 3D extended systems. These systems include arrays molecular hydrogen chains, as well coronene-type structures LiF 1D, 2D, 3D. Contrary to a recently proposed model it found that the persists all these cases. A simple explanation provided an analysis field-induced charges hydrogen, which shows excessive...

The method of calculating distributed polarizabilities is extended to the first and second dipole hyperpolarizabilities, in order describe more accurately molecular response strong inhomogeneous external time-dependent electric fields. dipolar expressed terms both potential related charge-density functions field dipole-density functions. macroscopic linear, quadratic, cubic optical susceptibilities crystals are (hyper) polarizabilities. This formulation differs from previous theories using...

A general reduced dimensionality finite field nuclear relaxation method for calculating vibrational nonlinear optical properties of molecules with large contributions due to anharmonic motions is introduced. In an initial application the umbrella (inversion) motion NH3 it found that difficulties associated a conventional single well treatment are overcome and particular definition inversion coordinate not important. Future applications described.

Human immunodeficiency virus type 1 protease (HIV-1 PR) is one of the main targets toward AIDS therapy. We have selected potent drug darunavir and a weak inhibitor (fullerene analog) as HIV-1 PR substrates to compare protease's conformational features upon binding. Molecular dynamics (MD), molecular mechanics Poisson-Boltzmann surface area (MM-PBSA), quantum-mechanical (QM) calculations indicated importance stability flaps effective binding: may induce flexibility flaps, which convert...

Static excited-state polarisabilities and hyperpolarisabilities of three Ru(II) ammine complexes are computed at the density functional theory (DFT) several correlated ab initio levels. Most accurate modelling low energy electronic absorption spectrum is obtained with hybrid functionals B3LYP, B3P86 or M06 for complex [Ru(II)(NH3)5(MeQ(+))](3+) (MeQ(+)=N-methyl-4,4'-bipyridinium, 3) in acetonitrile. The match experimental data less good [Ru(II)(NH3)5L](3+) (L=N-methylpyrazinium, 2;...

The main goal of this study was the design/recognition a series derivatives with exceptionally large hyperpolarizabilities, understanding mechanism through which these properties are derived, and generalization resulting findings. Thus, we have studied structure, involving excitation energies diradical character, but mainly (hyper)polarizabilities some oligomers radiaannulene-tetrathiafulvalene (RA-TTF), radiaannulene-bis(ethylene-1,2-dithiolato)nickel (RA-NiBDT), their lithiated analogues....

Geometries, inversion barriers, static and dynamic electronic vibrational dipole polarizability (α), first (β) second (γ) hyperpolarizability of the pyrrole homologues C4H4XH (X = N, P, As, Sb, Bi) have been calculated by Hartree−Fock, Møller−Plesset second-order perturbation theory, coupled-cluster theory accounting for singles, doubles, noniterative triple excitations methods, as well density functional using B3LYP PBE1PBE functionals Sadlej's Pol 6-311G** basis sets. Relativistic effects...

Abstract Electronic and vibrational nuclear relaxation (NR) contributions to the dipole (hyper)polarizabilities of endohedral fullerene Li@C 60 its monovalent cation [Li@C ] + are calculated at (U)B3LYP level. Many results new, while others differ significantly from those reported previously using more approximate methods. The properties compared with corresponding hypothetical noninteracting systems a valence electron transferred Li cage. Whereas NR contribution static linear...

Human serum albumin (HSA) is the most abundant blood plasma protein, which transports fatty acids, hormones, and drugs. We consider nanoparticle-HSA interactions by investigating binding of HSA with three fullerene analogs. Long MD simulations, quantum mechanical (fragment molecular orbital, energy decomposition analysis, atoms-in-molecules), free methods elucidated mechanism in these complexes. Such a systematic study valuable due to lack comprehensive theoretical approaches date. The main...

For the computation of rovibrational levels and their spectroscopic intensities, Eckart conditions are essential to achieve optimal separation between rotation vibration. Dymarsky Kudin [J. Chem. Phys. 122, 124103 (2005)] proposed a procedure for simplified calculation matrix. In present work, we have adapted approach obtain kinetic energy operator in curvilinear coordinates using numerical but exact without resorting finite differences. Furthermore, modified this study molecular systems...

This is the first part of a study local field effects on (non)linear optical susceptibilities solutions para-nitroaniline (pNA) in three different solvents, cyclohexane (CH), 1,4-dioxane (DI), and tetrahydrofuran (THF), using discrete molecular representation condensed phase. To account for dipolar quadrupolar effects, latter which are especially important DI solution, all electric properties necessary to compute fields gradients approximation as well hyperpolarizabilities four molecules...

Dipolar, dipole–quadrupole and quadrupole–quadrupole static polarizabilities of the water molecule have been determined by ab initio calculations at coupled cluster level theory with single, double perturbative triple excitations CCSD(T) an aug‐cc‐pVTZ basis set using a finite field field‐gradient method. The geometry dependence polarizability tensor components has explored modeled power series expansion in bond length angle variations up to sum powers equal 4. results provide very detailed...