Liq cryst online dating
Lattice metric singularities often involve lattices that are in a derivative relationship one to another. In actual cases like this, one can run into a trap.
The existence of such singularities, therefore, has a practical impact on the indexing of powder patterns. In fact, any rhombohedral cell of this kind has a derivative monoclinic subcell, each of which gives the same set of unique calculated cl-spacings.
"Ambiguities in powder pattern indexing: A ternary lattice metric singularity", A. Mighell,, Powder Diffraction, 16 (3): 144-1 Abstract: A lattice metric singularity occurs when unit cells defining, two (or more) lattices yield the identical set of unique calculated d-spacings. A singularity of this type is common and not a mathematical rarity.
(Including some non-100% relevant references that I want to follow up on later.) Note that 5 papers were found stating full-profile/whole-profile/whole profile based powder indexing. From the indexing point of view, both answers are correct.
The designed programs require no special software packages (except standard) and can be used in IBM-compatible computers with minimum resources.
The program complex is compared with its known analogs. Rossmann, Journal of Applied Crystallography, 1997, Vol.30, No. mf0013 "Diffraction pattern indexing and the effect of metal ion implantation on kappa-alumina", A.
Specified basis sets can be searched rapidly with the associated LOSHFZRF7 program (both programs are supported by CRYS2RUN)."Treor90 (Per-Eric Werner) (Reference: Werner, P.-E., Eriksson, L. (1985), TREOR, a Semi-Exhaustive Trial-and-Error Powder Indexing Program for All Symmetries, J.
When this happens, it is critical to recognize that there exists more than one indexing solution. "A new approach for indexing powder diffraction data based on whole-profile fitting and global optimization using a genetic algorithm", Benson M.
Tsang, Journal of Computational Chemistry, 1997, Vol.18, No.2, pp.290-299 "Refinement of the unit-cell parameters of a polycrystal using full-profile reflections recorded over a wide range of diffraction angles", V. Serykh, Industrial Laboratory, 1997, Vol.63, No.1, pp.22-25 "Powder Pattern Indexing", Marianne Westdahl, Giornate di Studio sulla Diffrattometria a Raggi X da Materiali Policristallini", Gargnano, Villa Feltrinelli, 20-22 marzo 1995, Universita degli Studi di Milano, Supplemento n.98, pp 156-175, (1995).
Cen perform automatic and manual cell and spacegroup assignment.
"CRYSFIRE is a simple script-based system for making existing indexing facilities more accessible to non-specialists, that runs with minimal demands under MSDOS or Windows.
It (a) performs an ITOv6 zone-search8, enhanced with Ishida & Watanabe's PM algorithm1, (b) completes Q(A, B, C, F) basis sets using Shirley's dominant-zone heuristic, (c) seeks Q(D, E) solutions for each basis set using exhaustive dichotomy algorithms from Lour & Shirley's LOSH program7, and finally (d) returns to Visser's ITOv68 for solution refinement and evaluation.
LZON is best for low-symmetry monoclinic and triclinic phases, particularly the pathological dominant-zone cases that can spawn hundreds of pseudo-solutions. Louer "Powder pattern indexing with the dichotomy method", J.