Computer calculation of the Van Vleck second moment for materials with internal rotation of spin groups
Description
Abstract This paper describes m2rc3, a program that calculates Van Vleck second moments for solids with internal rotation of molecules, ions or their structural parts. Only rotations about C_3axes of symmetry are allowed, but up to 15 axes of rotation per crystallographic unit cell are permitted. The program is very useful in interpreting NMR measurements in solids. Title of program: m2rc3 Catalogue Id: ADUC_v1_0 Nature of problem The NMR second moment reflects the strength of the nuclear magnetic dipole-dipole interaction in solids. This value can be extracted from the proper experiment and can be calculated on the basis of the Van Vleck formula. The internal rotation of molecules or their parts averages this interaction decreasing the measured value of the NMR second moment. The analysis of the internal dynamics based on the NMR second moment measurements is as follows. The second moment is measured at different tempera ... Versions of this program held in the CPC repository in Mendeley Data ADUC_v1_0; m2rc3; 10.1016/j.cpc.2004.06.071 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)