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Can a Finite Chain of Hydrogen Cyanide Molecules Model a Crystal?

Contribution

Chieh‐Min Hsieh, Björn Grabbet, Felix Zeller, Sanna Benter, Tarek Scheele, Norman Sieroka & Tim Neudecker

2022

When calculating structural or spectroscopic properties of molecular crystals, the question arises whether it is sufficient to simulate only a single molecule or a small molecular cluster or whether the simulation of the entire crystal is indispensable. In this work we juxtapose calculations on the high-pressure structural properties of the (periodic) HCN crystal and chains of HCN molecules of finite length. We find that, in most cases, the behavior of the crystal can be reproduced by computational methods simulating only around 15 molecules. The pressure-induced lengthening of the C−H bond in HCN found in calculations on both the periodic and finite material are explained in terms of orbital interaction. Our results pave the way for a more thorough understanding of high-pressure structural properties of materials and give incentives for the design of materials that expand under pressure. In addition, they shed light on the complementarity between calculations on periodic materials and systems of finite size.

ChemPhysChem 23(23).

DOI: 10.1002/cphc.202200414

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interstice

“The contradiction of law in Derrida lies in the interstice that separates the impossibility of deconstructing justice from the possibility of deconstructing law.”

Andreas Fischer-Lescano
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every day

“Living in contradictions is what we experience every day. Why do we know so little about it?”

Gisela Febel
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“If social contradictions are reflected in law, law cannot form a hierarchy of norms free of contradictions.”

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