Cartesian constraints in QM/MM optimizations

© 2023 The Authors. Journal of Computational Chemistry published by Wiley Periodicals LLC.

Bibliographische Detailangaben
Veröffentlicht in:Journal of computational chemistry. - 1984. - 44(2023), 30 vom: 15. Nov., Seite 2358-2368
1. Verfasser: López-Sosa, L (VerfasserIn)
Weitere Verfasser: Calaminici, P, Köster, A M
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2023
Zugriff auf das übergeordnete Werk:Journal of computational chemistry
Schlagworte:Journal Article ADFT QM/MM constrained optimization deMon2k normal coordinate space
Beschreibung
Zusammenfassung:© 2023 The Authors. Journal of Computational Chemistry published by Wiley Periodicals LLC.
With the rise of quantum mechanical/molecular mechanical (QM/MM) methods, the interest in the calculation of molecular assemblies has increased considerably. The structures and dynamics of such assemblies are usually governed to a large extend by intermolecular interactions. As a result, the corresponding potential energy surfaces are topological rich and possess many shallow minima. Therefore, local structure optimizations of QM/MM molecular assemblies can be challenging, in particular if optimization constraints are imposed. To overcome this problem, structure optimization in normal coordinate space is advocated. To do so, the external degrees of freedom of a molecule are separated from the internal ones by a projector matrix in the space of the Cartesian coordinates. Here we extend this approach to Cartesian constraints. To this end, we devise an algorithm that adds the Cartesian constraints directly to the projector matrix and in this way eliminates them from the reduced coordinate space in which the molecule is optimized. To analyze the performance and stability of the constrained optimization algorithm in normal coordinate space, we present constrained minimizations of small molecular systems and amino acids in gas phase as well as water employing QM/MM constrained optimizations. All calculations are performed in the framework of auxiliary density functional theory as implemented in the program deMon2k
Beschreibung:Date Revised 03.10.2023
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1096-987X
DOI:10.1002/jcc.27202