Theoretically derived thermodynamic properties can be improved by the refinement of low-frequency modes against X-ray diffraction data

Hoser, Anna A.; Sztylko, Marcin; Trzybiński, Damian; Madsen, Anders Ø.

doi:10.1039/d1cc02608a

Cited by 6 publications

(7 citation statements)

References 28 publications

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“…heat capacities), and these results are generally in good agreement with those obtained through adiabatic calorimetry measurements (see Fig. 8) (Hoser & Madsen, 2017;Sovago et al, 2020;Hoser et al, 2021). Furthermore, the refinement method was also recently combined with periodic DFT computations to determine the enthalpic and entropic contributions to the free energies of four pyrazinamide polymorphs, thus allowing the prediction of their stability order as a function of temperature and of the corresponding solid-state phase transitions (Hoser et al, 2022).…”

Section: Wavefunction-and Density-matrix-based Approachessupporting

confidence: 74%

Current developments and trends in quantum crystallography

Krawczuk,

Genoni

2024

Acta Crystallogr B Struct Sci Cryst Eng Mater

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Quantum crystallography is an emerging research field of science that has its origin in the early days of quantum physics and modern crystallography when it was almost immediately envisaged that X-ray radiation could be somehow exploited to determine the electron distribution of atoms and molecules. Today it can be seen as a composite research area at the intersection of crystallography, quantum chemistry, solid-state physics, applied mathematics and computer science, with the goal of investigating quantum problems, phenomena and features of the crystalline state. In this article, the state-of-the-art of quantum crystallography will be described by presenting developments and applications of novel techniques that have been introduced in the last 15 years. The focus will be on advances in the framework of multipole model strategies, wavefunction-/density matrix-based approaches and quantum chemical topological techniques. Finally, possible future improvements and expansions in the field will be discussed, also considering new emerging experimental and computational technologies.

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Section: Wavefunction-and Density-matrix-based Approachessupporting

confidence: 74%

Current developments and trends in quantum crystallography

Krawczuk,

Genoni

2024

Acta Crystallogr B Struct Sci Cryst Eng Mater

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“…Thus, for the pyrazinamide polymorphs we apply a recently developed quantum crystallography method (Genoni et al, 2018), coined Dynamic Quantum Crystallography, of estimating vibrational entropy and enthalpy from frequencies refined against single crystal X-ray diffraction data (Hoser & Madsen, 2016;. We term this refinement a normal-mode refinement (NoMoRe), and in recent years we have explained, validated, and applied this approach to various systems to estimate thermodynamic properties (Hoser et al, 2021;Sovago et al, 2020;Kofoed et al, 2019).…”

Section: Entropic Contribution To Thermodynamic Stabilitiesmentioning

confidence: 99%

Dynamics and disorder: on the stability of pyrazinamide polymorphs

Hoser¹,

Rekis²,

Madsen³

2022

Acta Crystallogr B Struct Sci Cryst Eng Mater

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This article focuses on the structure and relative stability of four pyrazinamide polymorphs. New single crystal X-ray diffraction data collected for all forms at 10 K and 122 K are presented. By combining periodic ab initio DFT calculations with normal-mode refinement against X-ray diffraction data, both enthalpic and entropic contributions to the free energy of all polymorphs are calculated. On the basis of the estimated free energies, the stability order of the polymorphs as a function of temperature and the corresponding solid state phase transition temperatures are anticipated. It can be concluded that the α and γ forms have higher vibrational entropy than that of the β and δ forms and therefore they are significantly more stabilized at higher temperatures. Due to the entropy which arises from the disorder in γ form, it overcomes form α and is the most stable form at temperatures above ∼500 K. Our findings are in qualitative agreement with the experimental calorimetry results.

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“…Therefore, the calculated À-point displacement patterns are fixed and their low-energy frequencies optimized to best explain the observed ADPs. The approach is harmonic and based on data measured at a single temperature, usually 100 K (Hoser et al, 2021). The model represents an average over the Brillouin zone.…”

Section: Atomic and Molecular Motion: Harmonic Quasiharmonic Anharmon...mentioning

confidence: 99%

Crystal structures

Bürgi¹

2022

Acta Crystallogr Sect B

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A personal view is offered on various solved and open problems related to crystal structures: the present state of reconstructing the crystal electron density from X-ray diffraction data; characterization of atomic and molecular motion from a combination of atomic displacement parameters and quantum chemical calculations; Bragg diffraction and diffuse scattering: twins, but different; models of real (as opposed to ideal) crystal structures from diffuse scattering; exploiting unexplored neighbourhoods of crystallography to mathematics, physics and chemistry.

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Theoretically derived thermodynamic properties can be improved by the refinement of low-frequency modes against X-ray diffraction data

Abstract: A framework for estimation of thermodynamic properties for molecular crystals via refinement of frequencies from DFT calculations against X-ray diffraction data is presented. The framework provides an efficient approach to...

Cited by 6 publications

References 28 publications

Current developments and trends in quantum crystallography

Current developments and trends in quantum crystallography

Dynamics and disorder: on the stability of pyrazinamide polymorphs

Crystal structures

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