Self-consistent field convergence for proteins: a comparison of full and localized-molecular-orbital schemes

Journal article


Publication Details

Author(s): Wick C, Hennemann M, Stewart JJP, Clark T
Journal: Journal of Molecular Modeling
Publisher: Springer Verlag (Germany)
Publication year: 2014
Volume: 20
Journal issue: 3
Pages range: 2159
ISSN: 1610-2940


Abstract


Proteins in the gas phase present an extreme (and unrealistic) challenge for self-consistent-field iteration schemes because their ionized groups are very strong electron donors or acceptors, depending on their formal charge. This means that gas-phase proteins have a very small band gap but that their frontier orbitals are localized compared to “normal” conjugated semiconductors. The frontier orbitals are thus likely to be separated in space so that they are close to, but not quite, orthogonal during the SCF iterations. We report full SCF calculations using the massively parallel EMPIRE code and linear scaling localized-molecular-orbital (LMO) calculations using Mopac2009. The LMO procedure can lead to artificially over-polarized wavefunctions in gas-phase proteins. The full SCF iteration procedure can be very slow to converge because many cycles are needed to overcome the over-polarization by inductive charge shifts. Example molecules have been constructed to demonstrate this behavior. The two approaches give identical results if solvent effects are included.



FAU Authors / FAU Editors

Clark, Timothy apl. Prof. Dr.
Computer-Chemie-Centrum
Hennemann, Matthias Dr.
Computer-Chemie-Centrum
Wick, Christian Dr.
Computer-Chemie-Centrum


Additional Organisation
Exzellenz-Cluster Engineering of Advanced Materials


External institutions with authors

Stewart Computational Chemistry


Research Fields

A3 Multiscale Modeling and Simulation
Exzellenz-Cluster Engineering of Advanced Materials


How to cite

APA:
Wick, C., Hennemann, M., Stewart, J.J.P., & Clark, T. (2014). Self-consistent field convergence for proteins: a comparison of full and localized-molecular-orbital schemes. Journal of Molecular Modeling, 20(3), 2159. https://dx.doi.org/10.1007/s00894-014-2159-y

MLA:
Wick, Christian, et al. "Self-consistent field convergence for proteins: a comparison of full and localized-molecular-orbital schemes." Journal of Molecular Modeling 20.3 (2014): 2159.

BibTeX: 

Last updated on 2018-10-08 at 01:27