The theory of dielectrics brought in by Onsager [1], which takes into account the interaction between molecules and their environment, though applicable to pure polar liquids, is inadequate to justify the behaviour of some liquids whose molecules exhibit associating properties, such as acids, alcohols, amides and cyanides. This inadequacy led Kirk­ wood [2] to hypothesize an orientational corre...

Absorption and fluorescence spectra of quinine sulphate (QSD) have been recorded at room temperature in wide range of solvents of different polarities. The ground-state dipole moment of QSD was obtained from quantum mechanical calculations and the excited state dipole moment of QSD was estimated from Bakhshiev’s and Kawski-Chamma-Viallet’s equations by means of solvatochromic shift method. High...

We use ab initio molecular dynamics simulation to calculate the dipole moment of water molecules in one-dimensional hydrogen bonded chains in narrow pores. The electronic charges are partitioned among the water molecules using maximally localized Wannier functions. For water molecules confined to the interior of a carbon nanotube we find an average dipole moment of about 2.7 D, almost 10 % lowe...

nbo analysis and density functional theory (dft: b3lyp/6-311+g**) based method were used to study the impacts of the anomeric effects (ae) on the conformational properties of 2-methoxy-1,2,4,5-tetrahydro-benzo[d]oxepine (1), -thiepine (2) and -selenepine (3). the gibbs free energy difference (geq–gax) values (i.e. δgeq-ax) at 298.15 k and 1 atm between the axial and equatorial conformations inc...

Line strengths have been calculated in the form of Einstein A coefficients and f-values for a large number of bands of the A2Π–X2Σ+ and B2Σ+–X2Σ+ systems and rovibrational transitions within the X2Σ+ state of CN using Western’s pgopher program. The J dependence of the transition dipole moment matrix elements (the Herman–Wallis effect) has been taken into account. Rydberg–Klein–Rees potential en...

It is well known that intense laser beams, when tuned near to a resonance, will often break up into an unpredictable distribution of hot spots and filaments. This beam breakup and filament formation is initiated by self-focusing, which, in turn, is caused by the intensitydependent refractive index [1]. In this Letter we show experimental results that demonstrate, at least for the near-ideal con...

Geomagnetic dipole moment variations associated with polarity reversals and excursions are expressed by large changes of the cosmogenic nuclide beryllium-10 (10Be) production rates. Authigenic 10Be/9Be ratios (proxy of atmospheric 10Be production) from oceanic cores therefore complete the classical information derived from relative paleointensity (RPI) records. This study presents new authigeni...

Valence topological charge-transfer (CT) indices are applied to the calculation of dipole moments. The algebraic and vector semisum CT indices are defined. The combination of CT indices allows the estimation of the dipole moments. The model is generalized for molecules with heteroatoms. The ability of the indices for the description of the molecular charge distribution is established by compari...

The structure and dynamics of luminescent excitons in tetracene thin films and nanoaggregates are investigated using time-resolved spectroscopy and theoretical calculations. The orientation of tetracene's transition dipole moment along its short molecular axis leads to properties qualitatively different from those observed in aggregates of phenylene-vinylene and thiophene oligomers, despite sim...

Potential energy and permanent dipole moment surfaces of the electronic ground state of formyl negative ion HCO(-) are determined for a large number of geometries using the coupled-cluster theory with single and double and perturbative treatment of triple excitations ab initio method with a large basis set. The obtained data are used to construct interpolated surfaces, which are extended analyt...