Results 221 to 230 of about 11,576,305 (269)

Modeling of the Reaction of Polyvinyl Alcohol With Water Using Semiempirical Quantum Chemical Methods of Computer Chemistry

Fibre Chemistry, 2001
Using the semiempirical PM3 quantum-chemical method, a model of the reaction of polyvinyl alcohol with water was constructed and the fundamental energy characteristics of the reaction were evaluated. The possibility of using computer modeling for studying the reaction of a plasticizer with polymer materials is demonstrated on the example of the ...
B A Izmailov, I A Abronin
exaly   +2 more sources

Proceeding on the riddles of ketene pyrolysis by applying ab initio quantum chemical computational methods in a detailed kinetic modeling study

Proceedings of the Combustion Institute, 2021
Abstract As ketene is a crucial intermediate for the high-temperature combustion of oxygenated hydrocarbons in general, an in-depth understanding of its chemistry is a fundamental requirement for the kinetic modeling of bio-based fuels. To gain a profound insight into the decomposition of ketene and subsequent reaction pathways high level ab initio ...
Heiko Minwegen, Malte Döntgen, Yann Fenard, Philipp Morsch, Karl Alexander Heufer   +4 more
openaire   +1 more source

Computational Tests of Quantum Chemical Models for Excited and Ionized States of Molecules with Phosphorus and Sulfur Atoms

The Journal of Physical Chemistry A, 2014
Time-dependent density functional theory (TD-DFT) and electron propagator theory (EPT) are used to calculate the electronic transition energies and ionization energies, respectively, of species containing phosphorus or sulfur. The accuracy of TD-DFT and EPT, in conjunction with various basis sets, is assessed with data from gas-phase spectroscopy.
David K, Hahn, Krishans, RaghuVeer, J V, Ortiz   +2 more
openaire   +2 more sources

Computer-aided estimation of kinetic rate constant for degradation of volatile organic compounds by hydroxyl radical: An improved model using quantum chemical and norm descriptors

Chemical Engineering Science, 2022
Abstract The kinetic rate constant of volatile organic compounds (VOCs) degradation represents an important parameter, which is valuable for evaluating the degradation efficiency and ecological risk of pollutants. In this study, the multiple-linear-regression method using quantum chemical and norm descriptors is utilized to develop a room-temperature
Yajuan Shi, Jin-Jin Li, Qiang Wang, Qingzhu Jia, Fangyou Yan, Zheng-Hong Luo, Yin-Ning Zhou   +6 more
openaire   +1 more source

Modeling Enzymatic Enantioselectivity Using Quantum Chemical Methodology

ACS Catalysis, 2020
The computational study of enantioselective reactions is a challenging task that requires high accuracy, as very small energy differences have to be reproduced.
Masoud Kazemi, Fahmi Himo, Ferran Planas
exaly   +2 more sources

Computational Quantum Chemistry of Chemical Kinetic Modeling

Journal of Chemical Engineering & Process Technology, 2016
The earth orbiting the sun, the electron bonded to a proton in the hydrogen atom are both manifestations of particles in motion bound by an inverse-square force and both are governed by the principle of least action (of all the possible paths the particles may take between two points in space and time, they take those paths for which the time integral ...
openaire   +1 more source

Computational Tests of Quantum Chemical Models for Structures, Vibrational Frequencies, and Heats of Formation of Molecules with Phosphorus and Sulfur Atoms

The Journal of Physical Chemistry A, 2010
The Gaussian-n, complete basis set, and Weizmann-1 quantum chemical models for heats of formation are applied to a set of molecules with relevance to the combustion or pyrolysis of chemical warfare materials. Most of these models generate standard deviations from experiment that are less than 2 kcal/mol.
David K, Hahn, Krishans S, RaghuVeer, J V, Ortiz   +2 more
openaire   +2 more sources

A COMPUTATIONAL GRID SYSTEM FOR QUANTUM CHEMICAL CALCULATIONS TESTED IN A MODELING OF THE GE(001) SURFACE

Journal of Theoretical and Computational Chemistry, 2005
A computational Grid system with the simple architecture was constructed based on Globus and the concept of web application for the quantum chemical calculation. The computational Grid provides interfaces to a web-based input module and several molecular orbital calculation packages.
Kwak, J, Lee, YS Lee, Yoon Sup
openaire   +1 more source

Electronic and Vibronic Spectra of Molecular Systems: Models and Simulations based on Quantum Chemically Computed Molecular Parameters.

2005
This chapter provides an overview on the models generally employed for the simulation of the vibronic spectra of molecules and on the level of theory necessary to obtain quantum-chemically reliable molecular parameters required for the simulations.
NEGRI, FABRIZIA, ORLANDI, GIORGIO
openaire   +2 more sources