one of the useful indices in molecular topology is randić index. the alternative double bonds andconjugation in the polyene compounds are one of the main properties in these compounds. someof the molecular orbital and structural properties refer to this specialty, such as: molar absorptioncoefficient (εmax) , electrical conductivity and difference energy level of the homo and lumoorbitals, etc....

Self assembled quantum dots have shown a great promise as a leading candidate for infrared detection at room temperature. In this paper, a theoretical model of the absorption coefficient of quantum dot devices is presented. Both of bound to bound absorption and bound to continuum absorption are taken into consideration in this model. This model is based on the effective mass theory and the Non ...

An analytical nonadiabatic approach has been developed to study the dimerization gap and the optical absorption coefficient of the Su-Schrieffer-Heeger model where the electrons interact with dispersive quantum phonons. By investigating quantitatively the effects of quantum phonon fluctuations on the gap order and the optical responses in this system, we show that the dimerization gap is much m...

The accurate, quantitative analysis of absorption and scattering properties in tissue is a central problem in biochemical optics, in particular for the determination of hemoglobin and oxyhemoglobin concentrations. Because of light scattering, the absolute concentrations of these chromophores (i.e., the absorption coefficient) cannot easily be inferred. A new method for the estimation of the abs...

We present a method for the measurement of small optical absorption coefficients. The method exploits the deformation of cavity Airy peaks that occur if the cavity contains an absorbing material with a nonzero thermorefractive coefficient dn/dT or a nonzero expansion coefficient α(th). Light absorption leads to a local temperature change and to an intensity-dependent phase shift, i.e., to a pho...