InfiniCharges: A tool for generating partial charges via the simultaneous fit of multiframe electrostatic potential (ESP) and total dipole fluctuations (TDF)

The InfiniCharges computer program, for generating reliable partial charges for molecular simulations in periodic systems, is here presented. This tool is an efficient implementation of the recently developed DM-REPEAT method, where the stability of the resulting charges, over a large set of fitting regions, is obtained through the simultaneous fit of multiple electrostatic potential (ESP) configurations together with the total dipole fluctuations (TDF). Besides DM-REPEAT, the program can also perform standard REPEAT fit and its multiframe extension (M-REPEAT), with the possibility to restrain the charges to an arbitrary value. Finally, the code is employed to generate partial charges for ZIF-90, a microporous material of the metal organic frameworks (MOFs) family, and an extensive analysis of the results is carried out. Program summary Program title: InfiniCharges Catalogue identifier: AEYJ-v1-0 Program summary URL:http://cpc.cs.qub.ac.UK/summaries/AEYJ-v1-0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License Version 3 No. of lines in distributed program, including test data, etc.: 385092 No. of bytes in distributed program, including test data, etc.: 4749285 Distribution format: tar.gz Programming language: Python, Fortran 90. Computer: PCs. Operating system: Linux. RAM: Megabytes to Gigabytes depending on problem size Classification: 16.13. External routines: NumPy [1] Nature of problem: Generation of partial charges for classical simulations of periodic systems. Solution method: Simultaneous fit of electrostatic potential (ESP) and total dipole fluctuations (TDF). In particular the multiple ESP configurations can be fitted at once. Restrictions: Orthorhombic simulation cells Running time: It depends on the system size and on the number of ESP configurations used for the fit. Times reported in this paper vary from 20 s up to a couple of hours. References:T. E. Oliphant, Python for Scientific Computing, Computing in Science and Engineering 9 (3) (2007) 10-20.