The effective fragment molecular orbital method for fragments connected by covalent bonds

TY - JOUR

T1 - The effective fragment molecular orbital method for fragments connected by covalent bonds

AU - Svendsen, Casper Steinmann

AU - Fedorov, Dmitri G.

AU - Jensen, Jan Halborg

N1 - e41117

PY - 2012/7/23

Y1 - 2012/7/23

N2 - We extend the effective fragment molecular orbital method (EFMO) into treating fragments connected by covalent bonds. The accuracy of EFMO is compared to FMO and conventional ab initio electronic structure methods for polypeptides including proteins. Errors in energy for RHF and MP2 are within 2 kcal/mol for neutral polypeptides and 6 kcal/mol for charged polypeptides similar to FMO but obtained two to five times faster. For proteins, the errors are also within a few kcal/mol of the FMO results. We developed both the RHF and MP2 gradient for EFMO. Compared to ab initio, the EFMO optimized structures had an RMSD of 0.40 and 0.44 Å for RHF and MP2, respectively.

AB - We extend the effective fragment molecular orbital method (EFMO) into treating fragments connected by covalent bonds. The accuracy of EFMO is compared to FMO and conventional ab initio electronic structure methods for polypeptides including proteins. Errors in energy for RHF and MP2 are within 2 kcal/mol for neutral polypeptides and 6 kcal/mol for charged polypeptides similar to FMO but obtained two to five times faster. For proteins, the errors are also within a few kcal/mol of the FMO results. We developed both the RHF and MP2 gradient for EFMO. Compared to ab initio, the EFMO optimized structures had an RMSD of 0.40 and 0.44 Å for RHF and MP2, respectively.

U2 - 10.1371/journal.pone.0041117

DO - 10.1371/journal.pone.0041117

M3 - Journal article

C2 - 22844433

SN - 1932-6203

VL - 7

JO - P L o S One

JF - P L o S One

IS - 7

ER -