An empirical correction for absorption anisotropy

Abstract

A least-squares procedure is described for modeling an empirical transmission surface as sampled by multiple symmetry-equivalent and/or azimuth rotation-equivalent intensity measurements. The fitting functions are sums of real spherical harmonic functions of even order, Ylm(-UO) + Ylm(Ul), 2 < l = 2n _< 8. The arguments of the functions are the components of unit direction vectors, -u0 for the reverse incident beam and Ul for the scattered beam, referred to crystal-fixed Cartesian axes. The procedure has been checked by calculations against standard absorption test data.

Synthesis, structural characterization and cytotoxic activity of ternary copper(II)–dipeptide–phenanthroline complexes. A step towards the development of new copper compounds for the treatment of cancer

“…The structures were solved by direct methods using the SIR-92 program [18] and the model refined with SHELXL-2013 [19]. Gaussian absorption correction was applied for complexes C4 and C6, whereas multi-scan correction was applied to complexes C3 and C5 [20,21]. SHELXL-2013 and ORTEP-3 programs were used within the WinGX [22] interface to prepare materials for publication.…”

The crystal structures of the low-temperature and high-pressure polymorphs of nitric acid

“…18 Absorption corrections were carried out using the multiscan procedure SAD-ABS. 19, 20 The structure of nitric acid at 210 K was solved by direct methods 21 and refined by full-matrix least-squares against F 2 using all data. 22 Hydrogen atoms were located in difference maps and all OH distances were refined with a distance restraint of 0.82(5) Å .…”

Multimetallic Arrays: Bi-, Tri-, Tetra-, and Hexametallic Complexes Based on Gold(I) and Gold(III) and the Surface Functionalization of Gold Nanoparticles with Transition Metals

“…38 Intensities were corrected for absorption effects by the multi-scan method based on multiple scans of identical and Laue equivalent reflections (using the SORTAV software). 39 Where possible non-hydrogen atoms were refined with anisotropic displacement parameters and the hydrogen atoms were positioned geometrically and refined using a riding model. In the case of the disordered hexafluorophosphate anion, and the partially occupied ether solvent molecule, anisotropic refinement was not possible, so they were modeled with isotropic displacement parameters.…”