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Unconstrained calculation program

Optimization of Unconstrained Olnective Assume the objective Func tion F is a function of independent variables i = r. A computer program, given the values for the independent variables, can calculate F and its derivatives with respect to each Uj. Assume that F is well approximated as an as-yet-unknown quadratic function in u. [Pg.485]

The first type of program, based on an unconstrained force field approach is more comprehensive but suffers from the limitation of the size of molecules that can be investigated due to the extent of computations needed. It is thus very apt for the study of smaller molecules or systems of molecules up to 40-60 atoms, but this limitation is also fictitious because it really depends on the capacity and calculation rate of the computer used. Such unconstrained force field programs tend to suffer furthermore from the problem that the automatic search for the minimum of energy might lead the program to minimize on a local rather than total minimum, and if particular attention is not exercised completely false results can be obtained (the black-box syndrome). [Pg.165]


See other pages where Unconstrained calculation program is mentioned: [Pg.155]    [Pg.203]    [Pg.246]    [Pg.159]    [Pg.2177]   
See also in sourсe #XX -- [ Pg.391 , Pg.392 ]




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Unconstrained

Unconstrained program

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