Boyd force field

The success of the gas phase electron diffraction analysis of cis-and /ra 5-decalin (123) is another example of the use of MM calculations as an auxiliary technique. Minimum energy conformations and vibrational ampUtudes were calculated by both the Lifson and Boyd force fields (30,31) and were used as the starting values for refinement of the geometrical and vibrational parameters for the least-squares analysis. The results revealed no appreciable strain in cj5-decalin (123) other than that expected from gauche interactions. 

In the study by Anet and Anet the abilities of nine different force fields were tested to reproduce geometry and energy data on a single molecule cis-sy -cis-perhydroanthracene. The aim of this study was to test the performance of force fields with experimental data not available at the time of force field parameterization. Experimental conformational energy data (inversion energy barrier) was best reproduced by the Boyd force field, followed by MM2 and the White-Bovill force field. Except for MM2, the force fields included in this study are not extensively used today. A discussion of these earlier force fields has been published. ... 

M. Jalaie, K. B. Lipkowitz, Published force field parameters for molecular mechanics, molecular dynamics, and Monte Carlo simulations, in Reviews in Computational Chemistry, Vol. 14, K.B. Lipkowitz, D. B. Boyd (Eds.), Wiley-VCH, New York, 2000, pp. 441-486. 

Landis C R, D M Root and T Cleveland 1995. Molecular Mechanics Force Fields for Modeling Inorgani and Organometallic Compounds. In Lipkowitz K B and D B Boyd (Editors). Reviews in Compute tional Chemistry Volume 6. New York, VCH Publishers, pp. 73-148. 

MOLECULAR BUILDER. One of the earliest successful MM programs by Boyd (37) has been used as a prototype of several other force field programs. For example, a modified version is in-... 

Exhaustive catalytic hydrogenation of triptycene affords an equilibrium mixture of perhydrotriptycene isomers. As expected, Boyd s force field (37) calculations, with a modified torsional constant, reproduced the observed composition fairly well (Table 6). All important conformations were taken into account for each isomer. The most stable conformations agree with the results of the X-ray analysis (131) and have the characteristic that the cyclohexane rings are invariably either boat or deformed chair. The most stable conformation of all is 20 (ttt). The predominant conformation of ccc, in which all cyclohexane rings are boat, has an enthalpy only 2.56 kcal/mol above that of 20. The difference is virtually all due to angle and torsional terms. 

Three MM programs are reported to be able to handle metal chelates (Table 10). Those originating from Boyd s force field do not consider nonbonded interactions beyond 1.2 times the sum of the van der Waals radii (218-221). Rasmussen s version of CFF is much more sophisticated (33,222). However, none of them explicitly considers induced bond dipoles in chelate ions that contain a number of highly polar bonds. This is probably why the previous calculations of metal chelates only compare closely related isomeric structures having the same metal ion. 

Pettersson, 1. and Liljefors, T. 1996. Molecular Mechanics Calculated Conformational Energies of Organic Molecules A Comparison of Force Fields , in Reviews in Computational Chemistry, Vol. 9, Lipkowitz, K. B. and Boyd, D. B., Eds., VCH New York, 167. 

Dinur U, Hagler AT. New approaches to empirical force fields. In Lipkowitz KB, Boyd DB, eds. Reviews in Computational Chemistry. Vol. 2. New York VCH, 1991 99 164. 

Pettersson I, Liljefors T. Molecular mechanics calculated conformational energies of organic molecules a comparison of force fields. In Lipkowitz KB, Boyd DB, eds. Reviews in Computational Chemistry. Vol. 9. New York VCH, 1996 167-189. Liljefors T, Gundertofte K, Norrby PO, Pettersson I. Molecular mechanics and comparsion of force fields. In Bultinck P, Winter HD, Langenaeker W, Tollenaere JP, eds. Computational Medicinal Chemistry for Drug Discovery. New York Marcel Dekker, 2004 1-28. 

J. Wang, R. J. Boyd, and A. Laaksonen, J. Cbem. Pbys., 104, 7261. A Hybrid Quantum Mechanical Force Field Molecular Dynamics Simulation of Liquid Methanol Vibrational Frequency Shifts as a Probe of the Quantum Mechanical/Molecular Mechanical Coupling. 

G. D. Smith and R. H. Boyd, Macromolecules, 23,1527 (1990). A Force Field for Conformational Energy Calculations on Ester Group Containing Polymers. 

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