Hirshfeld atom refinement based on projector augmented wave densities with periodic boundary conditions

Ruth, Paul Niklas; Herbst‐Irmer, Regine

doi:10.1107/s2052252522001385

Cited by 17 publications

(27 citation statements)

References 83 publications

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“…(ii) Second, rather than use a molecule-based procrystal wavefunction, one might want to use a fully periodic wavefunction, since such a wavefunction incorporates long-range electrostatic crystal field effects. This was achieved by Wall (2016) and Ruth et al (2022) for HAR-like refinement. In general, such infinite-periodic quantum mechanical methods are more time-consuming to compute owing to the necessity to perform Ewald sums.…”

Section: Technical Points Concerning the Xcw Methodsmentioning

confidence: 99%

X-ray constrained wavefunctions based on Hirshfeld atoms. I. Method and review

Davidson¹,

Grabowsky²,

Jayatilaka³

2022

Acta Crystallogr B Struct Sci Cryst Eng Mater

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The X-ray constrained wavefunction (XCW) procedure for obtaining an experimentally reconstructed wavefunction from X-ray diffraction data is reviewed. The two-center probability distribution model used to perform nuclear-position averaging in the original paper [Grimwood & Jayatilaka (2001). Acta Cryst. A57, 87–100] is carefully distinguished from the newer one-center probability distribution model. In the one-center model, Hirshfeld atoms are used, and the Hirshfeld atom based X-ray constrained wavefunction (HA-XCW) procedure is described for the first time, as well as its efficient implementation. In this context, the definition of the related X-ray wavefunction refinement (XWR) method is refined. The key halting problem for the XCW method – the procedure by which one determines when overfitting has occurred – is named and work on it reviewed.

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Section: Technical Points Concerning the Xcw Methodsmentioning

confidence: 99%

X-ray constrained wavefunctions based on Hirshfeld atoms. I. Method and review

Davidson¹,

Grabowsky²,

Jayatilaka³

2022

Acta Crystallogr B Struct Sci Cryst Eng Mater

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“…density and the development of software, for example, the recently published work on HAR with periodic DFT calculations with the projector augmented wave method (Ruth et al, 2022), or new implementations of DiSCaMB (Chodkiewicz et al, 2018) in CRYSTALS (Betteridge et al, 2003); however, in this latter case its related functionality is not yet publicly available.…”

Section: Introductionmentioning

confidence: 99%

Influence of modelling disorder on Hirshfeld atom refinement results of an organo-gold(I) compound

Pawlędzio¹,

Malińska²,

Kleemiss³

et al. 2022

IUCrJ

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Details of the validation of disorder modelling with Hirshfeld atom refinement (HAR) for a previously investigated organo-gold(I) compound are presented here. The impact of refining disorder on HAR results is discussed using an analysis of the differences of dynamic structure factors. These dynamic structure factor differences are calculated from thermally smeared quantum mechanical electron densities based on wavefunctions that include or exclude electron correlation and relativistic effects. When disorder is modelled, the electron densities stem from a weighted superposition of two (or more) different conformers. Here this is shown to impact the relative importance of electron correlation and relativistic effect estimates expressed by the structure factor magnitudes. The role of disorder modelling is also compared with the effect of the treatment of hydrogen anisotropic displacement parameter (ADP) values and atomic anharmonicity of the gold atom. The analysis of ADP values of gold and disordered carbon atoms showed that the effect of disorder significantly altered carbon ADP values and did not influence those of the gold atom.

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“…It may be followed by interpreting the diffraction data with more refined descriptions of the atomic and bonding electron densities, such as multipole models (MMs) (Stewart, 1976;Hansen & Coppens, 1978) or quantum mechanical Hirshfeld atom refinements (HARs) (Jayatilaka & Dittrich, 2008;Capelli et al, 2014;Kleemiss et al, 2021). They are usually based on Hartree-Fock (HF) or density functional theory (DFT) calculations, with or without consideration of the environment of the structural fragment that may also be treated quantum mechanically (Jayatilaka & Dittrich, 2008;Wieduwilt et al, 2021;Ruth et al, 2022). HAR at correlated levels has also been attempted (Wieduwilt et al, 2020).…”

Section: Introductionmentioning

confidence: 99%