The anatomy of a comprehensive constrained, restrained refinement program for the modern computing environment –Olex2dissected

Abstract

This paper describes the mathematical basis for olex2.refine, the new refinement engine which is integrated within the Olex2 program. Precise and clear equations are provided for every computation performed by this engine, including structure factors and their derivatives, constraints, restraints and twinning; a general overview is also given of the different components of the engine and their relation to each other. A framework for adding multiple general constraints with dependencies on common physical parameters is described. Several new restraints on atomic displacement parameters are also presented.

Intramolecular and intermolecular bromine⋯polyfluoroarene interactions: The crystal structure of bis{κC-1-(2,3,5,6-tetrafluoropyridyl)-3-benzylimidazolin-2-ylidene}tetrabromodimercury

“…The crystal was kept at 108.4(8) K during data collection. Using Olex2 [18], the structure was solved with the olex2.solve [19] structure solution programme using Charge Flipping and refined with the olex2.refine [19] refinement package using Gauss-Newton minimization. The non-hydrogen atoms were refined with anisotropic thermal parameters.…”

Magneto-Luminescence Correlation in the Textbook Dysprosium(III) Nitrate Single-Ion Magnet

“…The crystal was kept at 300 K during data collection. Using Olex2 [32], the structure was solved with the Superflip [33] structure solution program using Charge Flipping and refined with the olex2.refine [34] refinement package using Gauss-Newton minimisation.…”

Mechanism of Water Oxidation Catalyzed by a Dinuclear Ruthenium Complex Bridged by Anthraquinone

“…Absorption corrections were made using the multiscan technique. The structure was solved applying Olex2 [71] with the olex2.solve [72] structure solution program using charge flipping and refined with the olex2.refine [72] refinement package using Gauss-Newton minimization. All non-hydrogen atoms were refined anisotropically.…”