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High-pressure Nucleation of Low-Density Polymorphs*.

ABSTRACT: New polymorphs β and γ of bis-3-nitrophenyl disulphide, crystallized above 0.3 GPa, are less dense than the ambient-pressure polymorph α. This counterintuitive density relation results from the high-entropy nucleation and subsequent kinetic crystallization. The work performed by pressure compensates the high entropy and temperature product, substantiated in varied conformers and increased chemical potential. Pressure-increased viscosity promotes the kinetic polymorphs, in accordance with empirical Ostwald's rule of stages. It contrasts to mechanochemical techniques, favouring high-density polymorphs.

SUBMITTER: Sobczak S

PROVIDER: S-EPMC8252116 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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High-pressure Nucleation of Low-Density Polymorphs*.

Sobczak Szymon S Ratajczyk Paulina P Katrusiak Andrzej A

Chemistry (Weinheim an der Bergstrasse, Germany) 20210304 24

New polymorphs β and γ of bis-3-nitrophenyl disulphide, crystallized above 0.3 GPa, are less dense than the ambient-pressure polymorph α. This counterintuitive density relation results from the high-entropy nucleation and subsequent kinetic crystallization. The work performed by pressure compensates the high entropy and temperature product, substantiated in varied conformers and increased chemical potential. Pressure-increased viscosity promotes the kinetic polymorphs, in accordance with empiric ...[more]

PMID: 33506549

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