Mechamcs, molecular

Of all the methods that we will discuss in this book, quantum mechamcs is probably the most widely used and the most extensively developed. The importance of the subject can be gauged in many ways, from citation counts to the number of Nobel prizes awarded. The systems studied using quantum mechanics range from the simplest molecular species (e.g., HD+, H3) to some very large and complex molecules (e.g. DNA, proteins and... 

Nevins N, K Chen and N L Allinger 1996c Molecular Mechamcs (MM4) Vibrational Frequency Calculations for Alkenes and Conjugated Hydrocarbons. Journal of Computational Chemistry 17 730-746 Nicholas J B, A J Hopfmger, F R Trouw and L E Iton 1991 Molecular Modelling of Zeolite Structure. 2. Structure and Dynamics of Silica Sodalite and Silicate Force Field. The Journal of the American Chemical Society 113.4792-4800. 

Saunders M 1987 Stochastic Exploration of Molecular Mechamcs Energy Surface Hunting for the Global Minimum Journal cfthe American Chemical Society 109 3150-3152... 

The subscript i in Equation (11.86) refers to a quantum mechanical electron and the subscript a to a quantum mechamcal nucleus. The subscript M indicates a molecular mechanical nucleus and is its partial atomic charge. There are thus electrostatic interactions between the electrons of the quantum mechanical region and the molecular mechanical nuclei, electrostatic interactions between quantum mechanical and molecular mechanical nuclei, and van der Waals interactions between the quantum mechamcal and molecular mechanical atoms. The second and third terms in Equation (11.86) do not involve electronic coordinates and so can be calculated in a straightforward way (i.e. they are constant for a given nuclear configuration). The first term must be incorporated into the quantum mechanical calculation via one-electron integrals added to the one-electron matrix, These one-electron... 

Smgh U C and P A Kollman 1986. A Combined Ab Initio Quantum Mechamcal and Molecular Mechanical Method for Carrying out Simulations on Complex Molecular Systems Applications to the CHsQ + Q Exchange Reachon and Gas Phase Protonation of Polyethers. Journal of Computational Chemistry 7-718-730... 

Still W C, A Tempczyrk, R C Hawley and T Hendrickson 1990. Semianalytical Treatment of Solvation for Molecular Mechamcs and Dynamics. Journal of the American Chemical Society 112 6127-6129... 

Polymeric materials composed of flexible molecular chains respond very sensitively to changes in vanous surrounding conditions such as temperature, stress, pressure, and so on For example, temperature variation induces in polymeric materials drastic changes m mechamcal and electrical properties as well as the phase transitions of melting and crystallization. Since these phenomena are accompanied by considerable vanation in viscoelastic characteristics and thus in density (p) and elastic modulus (E) of the materials, the ultrasonic method which can detect quite sensitively these viscoelastic properties becomes one of the most valuable and important methods for investigating the macro- as well as microscopic structural changes occurring in the materials. 

Antes 1, Thiel W. On the treatment of link atoms in hybrid methods. In Gao J, Thompson MA, editors. Hybrid Quantum Mechanical and Molecular Mechamcal Methods Proceedings of ACS Symposium Series. Washington, DC ACS 1998. 712 50-65. 

Combined Quantum Mechanical and Molecular Mechanical Potentials Combined Quantum Mechanics and Molecular Mechanics Approaches to Chemical and Biochemical Reactivity Hybrid Methods Hybrid Quantum Mecha-nical/Molecular Mechamcal (QM/MM) Methods Linear Scaling Methods for Electronic Structure Calculations Protein Modeling Quantum Mechaniccd/Molecular Mechanical (QM/MM) Coupled Potentials Quantum Mecha-nics/Molecular Mechanics (QM/MM). 

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