Thermally stable, durable, insulative polyimides are in great demand for the fabrication of microelectronic devices. In this investigation dielectric and optical properties have been studied for several series of aromatic polyimides. The effect of polarizability, fluorine content, and free volume on dielectric constant was examined. In general, minimizing polarizability, maximizing free volume ...

The polarizabilities of Si clusters with 9 to 28 atoms are calculated using a density functional cluster method. The atomic geometries are based on those carefully optimized by energy minimization. The polarizability shows fairly irregular variation with cluster size, but all calculated values are higher than the polarizability of a dielectric sphere with bulk dielectric constant and equivalent...

The electric dipole polarizability of the lithium atom in the ground state is calculated including relativistic and quantum electrodynamics corrections. The obtained result αE = 164.074 0(5) a.u. is in a good agreement with the less accurate experimental value of 164.19(1.08) a.u. The small uncertainty of about 2ppm comes from the approximate treatment of quantum electrodynamics corrections. Ou...

A rigorous formalism for determining the electric dipole polarizability of a threehadron bound complex in the case that the system has only one bound (ground) state has been elaborated. On its basis, by applying a model wave function that takes into account specific features of the structure of the lightest hypernucleus and using the known low-energy experimental data for the p − n and Λ − d sy...

A comparison between an analytical calculation of the polarizability of a mesoscopic interacting system in the random phase approximation and numerical exact diagonalization results is presented. While for weak interactions the analytical calculation fits the numerical results rather well, deviations appear for stronger interactions. This is the result of the appearance of intermediate range co...

We report on a new optical technique that uses light forces and a time-of-flight spectrometer to make absolute measurements of cluster polarizabilities. This is also the first accurate report of an ac polarizability measurement of a condensable cluster in the gas phase. We have determined the optical polarizability of C60 at the fundamental wavelength of a Nd:YAG laser ~1.064 mm! to be a57964 Å...

High-resolution atomic-beam laser spectroscopy has been performed to study Stark effect of Ba atom. Stark spectra have been observed at various electric fields for Ba highly excited states. The scalar polarizability of the transition from 6s5d3D2 to 5d6p3F3 at 728.0 nm and the tensor polarizability of the 3F3 level have been determined for the first time, to be αs = −89.8 (12) kHz/(kV/cm)2 and ...

Recent attempts to detect the pion polarizability via analysis of γγ → ππ measurements are examined. The connection between calculations based on dispersion relations and on chiral perturbation theory is established by matching the low energy chiral amplitude with that given by a full dispersive treatment. Using the values for the polarizability required by chiral symmetry, predicted and experi...

The topological partitioning of electronic properties approach at Hartree-Fock level is used to investigate charge transfer response in a water dimer. Distributed polarizability components are employed to calculate the change in electron density under external fields. Field-induced charge flow between the water monomers is most significant along the direction of the hydrogen bond. The molecular...

A linear response of a molecule in excited state to an external electric field is discussed in terms of frequency dependent polarizabilities. Results of accurate calculations of polarizabilities of the hydrogen molecule in its b aL: and B lL/ states are presented. The results are compared with other ab initio and model calculations. It is shown that there is no contribution to the polarizabilit...