Results 231 to 240 of about 11,576,305 (269)

Quantum mechanical computational studies of chemical reactions : III. Collinear A + BC reaction with some model potential energy surfaces

Molecular Physics, 1973
The effects of the location of the energy barrier and of changing vibrational frequency along the reaction path on the reaction dynamics of a collinear A + BC → AB + C reaction were studied using a series of ‘diagnostic’ model potential energy surfaces.
Shiou-Fu Wu, B.R. Johnson, R.D. Levine
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Role of computer modelling in spectroscopic and quantum-chemical investigations of the structure and properties of polyatomic molecules

2009 International Conference on Application of Information and Communication Technologies, 2009
Investigations of the spatial and electronic structure as well as the study of the vibrational spectra of the different molecules by the methods of computer modeling are review in the given study.
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Accurate Chemical Reaction Modeling on a Noisy Intermediate-Scale Quantum Computer with an Active Space-Based Workflow

The Journal of Physical Chemistry Letters
Quantum computing offers a compelling route to ab initio simulations of chemical reactions, while noisy intermediate-scale quantum (NISQ) hardware demands resource-aware protocols. In this study, we introduce an efficient workflow using a noise-resilient hardware-adaptable ansatz (HAA) in an active space combined with driven similarity renormalization ...
Xiongzhi Zeng, Huili Zhang, Shizheng Zhang, Pei Liu, Kehuan Linghu, Jiangyu Cui, Xiaoxia Cai, Jie Liu, Zhenyu Li, Jinlong Yang   +9 more
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Hybrid HPC and quantum computing framework for multiscale modelling of chemical systems

We present a multiscale workflow for coupling quantum computing algorithms for quantum chemical calculations with conventional High-Performance Computing (HPC) software. The resulting embedding framework, implemented in the multiscale computational chemistry environment ChemShell, combines a generic N-layer subtractive Quantum Mechanics/Molecular ...
Joseph C R Thacker, Mateusz Meller, Alberto Popescu, Andrew Patterson, Róbert Izsák, Vendel Szeremi, Thomas W Keal   +6 more
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A Deep Insight into the Details of the Interisomerization and Decomposition Mechanism of o-Quinolyl and o-Isoquinolyl Radicals. Quantum Chemical Calculations and Computer Modeling

The Journal of Physical Chemistry A, 2016
The isomerization of o-quinolyl ↔ o-isoquinolyl radicals and their thermal decomposition were studied by quantum chemical methods, where potential energy surfaces of the reaction channels and their kinetics rate parameters were determined. A detailed kinetics scheme containing 40 elementary steps was constructed.
Faina, Dubnikova, Carmen, Tamburu, Assa, Lifshitz   +2 more
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Production of Aliphatic and Aromatic Compounds in the High Temperature Decomposition of Propargyl Chloride. Single Pulse Shock Tube Experiments, Quantum Chemical Calculations, and Computer Modeling

The Journal of Physical Chemistry A, 2019
The thermal reactions of propargyl chloride were studied behind reflected shock waves in a pressurized driver 2 in. i.d. single-pulse shock tube over the temperature range 1000-1350 K and pressure range behind the reflected shocks of 2-4 atm. Cooling rates were ∼5 × 105 K/s.
Faina Dubnikova, Carmen Tamburu, Assa Lifshitz   +2 more
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Electron affinities of p-benzoquinone, p-benzoquinone imine and p-benzoquinone diimine, and spin densities of their p-benzosemiquinones computed by several quantum chemical models.

Journal of computer-aided molecular design, 1997
Restricted and unrestricted (U) Hartree-Fock (HF), second-order Møller-Plesset perturbation (MP2), density functional (DF), hybrid HF/DF and semiempirical (half-electron (HE) method) models have been used to calculate adiabatic electron affinities (EAad values) of p-benzoquinone (I), p-benzoquinone imine (VI) and p-benzoquinone diimine (XI), as well as
Y H, Mariam, L, Chantranupong
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Family of V(III)-Tristhiolato Complexes Relevant to Functional Models of Vanadium Nitrogenase: Synthesis and Electronic Structure Investigations by Means of High-Frequency and -Field Electron Paramagnetic Resonance Coupled to Quantum Chemical Computations.

Inorganic Chemistry, 2009
A series of V(III) complexes of varying coordination number (5, 6, and 7) all containing the PS3 ligand (PS3 = trianion of tris(2-thiophenyl)phosphine and its derivatives with other phenyl substituents) has been prepared and structurally characterized. The complexes have general formula [V(PS3)L(n)](0,-), where n = 1 (from L = Cl(-), 1-Me-Im, N(3)(-)),
Ye, S., Neese, F., Ozarowski, A., Smirnov, D., Krzystek, J., Telser, J., Liao, J., Hung, C., Chu, W., Tsai, Y., Wang, R., Chen, K., Hsu, H.   +12 more
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Prediction of scanning tunneling microscope images by computational quantum chemistry: chemical models and software design

1993
We have created chemical models for predicting and interpreting STM images of several specific systems. Detailed studies are made of transition metal dichalcogenides (MoS_2 and MoTe_2), Xe on Ni (110), C_3H_4 on Ni (110) and n-butyl benzene on a graphite model (C_(42)O_6H_(12). In the case of MoS_2 we study the ambiguity in the STM images regarding the
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Model, Multiply Hydrogen-Bonded Water Oligomers (N = 3−20). How Closely Can a Separable, ab Initio-Grounded Molecular Mechanics Procedure Reproduce the Results of Supermolecule Quantum Chemical Computations?

The Journal of Physical Chemistry A, 1997
Several high-level quantum chemical calculations have highlighted the prominent weight of nonadditivity within the total stabilization energy of multiply hydrogen-bonded complexes, such as exemplified by water oligomers (reviewed in ref 1). We have evaluated the extent to which the SIBFA (sum of interactions between fragments ab initio computed ...
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