40 results about "Quantum chemical" patented technology

The invention discloses a method and application for constructing polarized force fields and a method and system for predicting drug crystal forms. The method for constructing chemical molecule polarized force fields is suitable for being executed in one or more computation apparatuses, and comprises the following steps of: carrying out optimization computation on a quantum chemical structure of a chemical molecule on the basis of an ab initio calculation method so as to obtain a locally optimized molecular structure; calculating the difference between first energy of the locally optimized molecular structure when the charge of the molecular structure is neutral and second energy of the locally optimized molecular structure when the molecular structure has a predetermined positive-valence charge, and taking the difference as a vertical ion potential corresponding to the molecular structure; calculating polarized force field parameters of the molecular structure on the basis of the vertical ion potential and the locally optimized molecular structure, wherein the polarized force field parameters comprise a multi-pole vector of atom distribution, a multi-pole polarization rate of the atom distribution and a frequency-related polarization rate; and constructing a corresponding polarized force field model on the basis of the locally optimized molecular structure and the calculated polarized force field parameters.

The invention discloses a method for quantitatively analyzing the photocatalytic performance of silver bromide clusters. The method is based on quantum chemical density functional theory to characterize and measure the photocatalytic performance of silver bromide clusters. Through the structural research of silver bromide clusters , to determine its stable structure, and analyze the electronic structure, absorption spectrum, and positions of valence and conduction bands of silver bromide clusters according to the energy band theory, and finally determine its photocatalytic performance. Combined with relevant experimental research literature, a method for characterizing and measuring the photocatalytic performance of clusters is summarized. The method does not require any experiments, and can characterize the photocatalytic performance of silver bromide clusters only by using quantum chemical theoretical calculation; the method can be extended to the measurement and characterization of photocatalytic performance of other photocatalysts.

The invention discloses a method for predicting the reduction rate constant of nitroaromatic compounds. On the basis of known compound structures, the molecular structure of nitroaromatic compounds is fully optimized by using Gaussian software package to obtain the molecular volume V m , the highest occupied orbital energy E HOMO , the lowest empty orbital energy E LUMO , Frontier orbital energy level difference △ E ,Dipole moment mu , molecular polarizability α , ionization potential I P Quantum chemical parameters such as the total energy of the compound are used as structural descriptors, and the obtained structural descriptors are combined with the data of the reduction rate, and the quantitative relationship between various structural descriptors and the reduction rate is established through the partial least squares stepwise linear regression method. relational equations to validate the model to assure its predictive power. The invention can simply, quickly and effectively predict the reduction rate constant of the nitroaromatic compound to be studied, and provide necessary basic data for the environmental persistence, ecological risk assessment and supervision of the nitroaromatic compound chemical.