Second-order current materials

The current review will present selected results on materials which appear to this author to have promise in NLO applications. Most references will be recent. The review will follow a format in which materials for linear optics are first reviewed very briefly, followed by a discussion of second order, then third order materials. 

For planar or spherical electrodes, where the mass transport is a diffusion function in one dimension, it is possible to solve the diffusion equation as a function of time. In Section 3 the principles of how the cyclic voltammetric peak current could be calculated for a simple electron transfer reaction were presented. It is also possible to solve the material balance equations for the spherical electrode at steady state for a few first-order mechanisms (Alden and Compton, 1997a). In order to tackle second-order kinetics, more complex mechanisms, solve time-dependent equations or model other geometries with... 

The CHETAH data bank contains data for about 500 group contributions and about 400 chemical compounds. The data stored for the current program is heavily oriented toward organic materials. Data for chemical compounds is stored for 1) common, frequently used molecules, 2) molecules which are too small to be estimated by second order groups, 3) common decomposition products, and 4) molecules which can be used as building blocks to create other molecules. The results for a typical heat of reaction calculation are shown in Table II. 

In this paper, a thermodynamic phase transition is studied using Differential Scanning Calorimetry (DSC). This phase transition, which will be described according to the current thermodynamic theories as a first order or a second order one, is recorded on the DSC trace as an anomalous change in the differential power ZP, different from the normal IP variation only due to the heat capacity of the material. This variation, sharp or smooth, will be called the "transition peak". We define the height h of the peak as the distance between the heat capacity trace, or baseline, and the maximum during the course of the phase transition. In the case of a pure second order phase transition, this height is the diffe-... 

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