Size and shape dependence of finite-volume Kirkwood-Buff integrals

Peter Krüger, Thijs J.H. Vlugt

Research output: Contribution to journalArticleScientificpeer-review

33 Citations (Scopus)


Analytic relations are derived for finite-volume integrals over the pair correlation function of a fluid, the so-called Kirkwood-Buff integrals. Closed-form expressions are obtained for cubes and cuboids, the system shapes commonly employed in molecular simulations. When finite-volume Kirkwood-Buff integrals are expanded over an inverse system size, the leading term depends on shape only through the surface area-to-volume ratio. This conjecture is proved for arbitrary shapes and a general expression for the leading term is derived. From this, an extrapolation to the infinite-volume limit is proposed, which converges much faster with system size than previous approximations and thus significantly simplifies the numerical computations.

Original languageEnglish
Article number051301
Number of pages5
JournalPhysical Review E
Issue number5
Publication statusPublished - 2018


Dive into the research topics of 'Size and shape dependence of finite-volume Kirkwood-Buff integrals'. Together they form a unique fingerprint.

Cite this