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[en] Electric and magnetic polarizabilities of pointlike spin-1/2 particles possessing an anomalous magnetic moment are calculated with the transformation of an initial Hamiltonian to the Foldy-Wouthuysen representation. Comparison of corresponding results for spin-1/2 and spin-1 particles is performed.
[ru]Электрическая и магнитная поляризуемости точечноподобных частиц со спином 1/2, имеющих аномальный магнитный момент, рассчитаны путем преобразования исходного гамильтониана к представлению Фолди-Ваутхойзена. Произведено сравнение соответствующих результатов для частиц со спинами 1/2 и 1.
[en] Highlights: * Performance of double-hybrid schemes is assessed for polarizability of ozone. * Parameterized and parameter-free double-hybrids are explored. * Best performing approximations are proposed for polarizability calculations. Literature survey on the electric response properties of ozone reveals that the accurate prediction of its dipole polarizability and resolving the discrepancies in this context is a challenging case to current structure theories. In this Letter, we report the results of approximations from the highest rung of Jacob's ladder, double-hybrid (DH) functionals, for dipole polarizability of ozone. Benchmarking the two families of DHs, parameterized and parameter-free models, we find that the functionals B2Ͽ-PLYP and PBE0-DH as empirical and nonempirical DHs, respectively, provide the results in line with those obtained from the high correlated ab initio approaches.
[en] Under intense optical excitation, the polarizability of transparent optical materials has a significant third order, nonlinear contribution. This manifests itself in a wide variety of effects, which, under certain conditions, are collectively referred to as white light continuum generation. We report on a new approach that isolates, for the first time, some of these effects
[en] Interfacial properties of an ionic fluid next to a uniformly charged planar wall are studied in the restricted primitive model by both theoretical and Monte Carlo methods. The system is a 1:1 fluid of equisized charged hard spheres in a state appropriate to 1M aqueous electrolyte solutions. The interfacial density profiles of counterions and coions are evaluated by extending the hypernetted chain approximation (HNC) to include the leading bridge diagrams for the wall-ion correlations. The theoretical results compare well with those of grand canonical Monte Carlo computations of Torrie and Valleau over the whole range of surface charge density considered by these authors, thus resolving the earlier disagreement between statistical mechanical theories and simulation data at large charge densities. In view of the importance of the model as a testing ground for theories of the diffuse layer, the Monte Carlo calculations are tested by considering alternative choices for the basic simulation cell and are extended so as to allow an evaluation of the differential capacitance of the model interface by two independent methods. These involve numerical differentiation of the mean potential drop as a function of the surface charge density or alternatively an appropriate use of a fluctuation theory formula for the capacitance. The results of these two Monte Carlo approaches consistently indicate an initially smooth increase of the diffuse layer capacitance followed by structure at large charge densities, this behaviour being connected with layering of counterions as already revealed in the density profiles reported by Torrie and Valleau. (author)
[en] Coupled-cluster calculations of the static electronic dipole polarizabilities and Cauchy moments are reported for all 15 halomethanes CHmClnF4−m−n. Comparison with available experimental static polarizabilities is made. Excluding three experimental values which seem to be in error, the mean absolute deviation between the CCSD(T) values and experiment is a rather satisfactory 0.5 atomic units for the remaining 11 halomethanes. More experimental work is needed for the polarizabilities of CHCl2F, CCl3F, and CH2Cl2. Additivity approximations work moderately well for α = S(−2) and progressively less well for S(−2k − 2) as k increases.
[en] The electromagnetic structure of charged pions can be described by the electric (απ) and magnetic (βπ) polarizabilities that depend on the rigidity of pion’s internal structure as a composite particle. It is shown that the values of απ and βπ can be precisely measured via the Primakoff reaction π- + (A, Z) → π- + (A, Z) + γ in the COMPASS experiment at CERN.