KAREP - a program for calculating irreducible space-group representations

Abstract

The category Computer Program Abstracts provides a rapid means of communicating up-to-date information concerning both new programs or systems and significant updates to existing ones. Following normal submission, a Computer Program Abstract will be reviewed by one or two members of the IUCr Commission on Crystallographic Computing. Itshould not exceed 500 words in length and should use the standard format given on page 189 of the June 1985

Bilbao Crystallographic Server. II. Representations of crystallographic point groups and space groups

“…The method. REPRES calculates the irreps of space groups following the algorithm applied in KAREP (Hovestreydt et al, 1992). Both programs apply a general scheme based on a normal-subgroup induction method of constructing the irreps of a group G starting from those of a normal subgroup H / G. The main steps of the procedure involve the construction of all irreps of H and their distribution into orbits under G, determination of the corresponding little groups and the allowed (small) irreps and, finally, construction of the irreps of G by induction from the allowed irreps.…”

Symmetry and magnetic structures

“…The basis functions of the irreps of G k can be calculated using the projection operator formula (17) particularised for the explicit expression of O(g) acting on the vectors { kj s } (equation 48). The explicit…”

G -type magnetic order in ferropnictide CuxFe1−yZou1, Lee2, Cao3 et al. 2017Phys. Rev. B2290View full textAdd to dashboardCite

“…The unusual temperature dependences of the (1 0 0.5) and (0 0 0.5) neutron scattering intensity described above imply different magnetic structures for temperature regions below and above T N2 , which are indeed revealed by the representational analysis using the BasIrreps program in FULLPROF [39,40]. For T < T N2 , a canted spin structure (Fig.…”