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Hartree-Fock method applications

The application of density functional theory to isolated, organic molecules is still in relative infancy compared with the use of Hartree-Fock methods. There continues to be a steady stream of publications designed to assess the performance of the various approaches to DFT. As we have discussed there is a plethora of ways in which density functional theory can be implemented with different functional forms for the basis set (Gaussians, Slater type orbitals, or numerical), different expressions for the exchange and correlation contributions within the local density approximation, different expressions for the gradient corrections and different ways to solve the Kohn-Sham equations to achieve self-consistency. This contrasts with the situation for Hartree-Fock calculations, wlrich mostly use one of a series of tried and tested Gaussian basis sets and where there is a substantial body of literature to help choose the most appropriate method for incorporating post-Hartree-Fock methods, should that be desired. [Pg.157]

Within the periodic Hartree-Fock approach it is possible to incorporate many of the variants that we have discussed, such as LFHF or RHF. Density functional theory can also be used. I his makes it possible to compare the results obtained from these variants. Whilst density functional theory is more widely used for solid-state applications, there are certain types of problem that are currently more amenable to the Hartree-Fock method. Of particular ii. Icvance here are systems containing unpaired electrons, two recent examples being the clci tronic and magnetic properties of nickel oxide and alkaline earth oxides doped with alkali metal ions (Li in CaO) [Dovesi et al. 2000]. [Pg.165]

The premise behind DFT is that the energy of a molecule can be determined from the electron density instead of a wave function. This theory originated with a theorem by Hoenburg and Kohn that stated this was possible. The original theorem applied only to finding the ground-state electronic energy of a molecule. A practical application of this theory was developed by Kohn and Sham who formulated a method similar in structure to the Hartree-Fock method. [Pg.42]

Bartlett, R. J., Stanton, J. F., 1995, Applications of Post-Hartree-Fock Methods A Tutorial , Rev. Comput. Chem., 5, 65. [Pg.280]

Bartlett RJ, Stanton JF (1994) Applications of post-hartree-fock methods a tutorial. In Lipkowitz KB Boyd DB (eds) Reviews in computational chemistry, vol. 5. Wiley-VCH, New York, pp 65—169... [Pg.328]

Rodney J. Bartlett and John F. Stanton, Applications of Post-Hartree-Fock Methods A Tutorial. [Pg.442]

Although HF theory is useful in its own right for many kinds of investigations, there are some applications for which the neglect of electron correlation or the assumption that the error is constant (and so will cancel) is not warranted. Post-Hartree-Fock methods seek to improve the description of the electron-electron interactions using HF theory as a reference point. Improvements to HF theory can be made in a variety of ways, including the method of configuration interaction (Cl) and by use of many-body perturbation theory (MBPT). It is beyond the scope of this text to treat Cl and MBPT methods in any but the most cursory manner. However, both methods can be introduced from aspects of the theory already discussed. [Pg.239]

The 13C chemical shift contour map for the Cp carbon of the L-alanine residue in peptides and polypeptides was made as a function of the dihedral angles(, W) by using the experimental data. Also, the corresponding calculated map was made by using the ab initio coupled Hartree-Fock method with the gauge included atomic orbitals(GIAO-CHF). From these results, it was found that the calculated map explains the chemical shift behavior of the a-helix and p-sheet forms in poly(L-alanine) and some proteins. This suggests that the calculated map is applicable to the structural analysis of proteins with complicated structure. [Pg.138]

Michel Dupuis, Proceedings of the Workshop on Recent Developments and Applications of Multi-Configuration Hartree-Fock Methods. Proceedings of a conference held at Texas A8cM University, July 15-17,1980, in National Resource for Computation in Chemistry Proceedings, No. 10, NTIS, Springfield, VA, 1981. [Pg.309]

M. M. Mestechkin, G. E. Vaiman, V. Klimo, et al., Extended Hartree-Fock Method and Its Application to Molecules, Naukova Dumka, Kiev, 1983. [Pg.310]

Application of the Hartree-Fock Method. - Since numerical Hartree-Fock programs dealing with complex numbers are available in many research groups, it seemed natural to apply this scheme also to the scaled Bom-Oppenheimer Hamiltonian (4.15). As a consequence, some numerical results were obtained before the theory was developed, and - as we have emphasized in the Introduction - some features seemed rather astonishing. [Pg.221]


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Hartree-Fock method

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