User Manual for MOLSCAT, BOUND and FIELD, Version 2020.0: programs for quantum scattering properties and bound states of interacting pairs of atoms and molecules
Abstract
MOLSCAT is a generalpurpose package for performing nonreactive quantum scattering calculations for atomic and molecular collisions using coupledchannel methods. Simple atommolecule and moleculemolecule collision types are coded internally and additional ones may be handled with plugin routines. Plugin routines may include external magnetic, electric or photon fields (and combinations of them). Simple interaction potentials are coded internally and more complicated ones may be handled with plugin routines. BOUND is a generalpurpose package for performing calculations of boundstate energies in weakly bound atomic and molecular systems using coupledchannel methods. It solves the same sets of coupled equations as \MOLSCAT, and can use the same plugin routines if desired, but with different boundary conditions. FIELD is a development of BOUND that locates external fields at which a bound state exists with a specified energy. One important use is to locate the positions of magnetically tunable Feshbach resonance positions in ultracold collisions. Versions of these programs before version 2019.0 were released separately. However, there is a significant degree of overlap between their internal structures and usage specifications. This manual therefore describes all three, with careful identification of parts that are specific to one or two of the programs.
 Publication:

arXiv eprints
 Pub Date:
 March 2019
 arXiv:
 arXiv:1903.06755
 Bibcode:
 2019arXiv190306755H
 Keywords:

 Physics  Chemical Physics;
 Condensed Matter  Quantum Gases;
 Physics  Atomic and Molecular Clusters;
 Physics  Atomic Physics
 EPrint:
 206 pages. Program source code available from https://github.com/molscat/molscat This is the full program documentation for the programs described in the journal papers Comp. Phys. Commun. 241, 18 (2019) (arXiv:1811.09111) and Comp. Phys. Commun. 241, 916 (2019) (arXiv:1811.09584). There is significant text overlap between some parts of the documentation and the (much shorter) journal papers