CalcOPP-3D 1.0.0

In the OPP approach, every atom is treated as an individual Einstein oscillator subject to Boltzmann statistics in the classical limit. The OPP itself represents the potential as experienced by an atom at a certain position and allows, <em>e.g.</em>, to assess the viability and activation barriers of migration pathways [see K. N. Trueblood, H.-B. Bürgi, H. Burzlaff, J. D. Dunitz, C. M. Gramaccioli, H. H. Schulz, U. Shmueli, S. C. Abrahams, <em>Acta Crystallogr., Sect. A: Found. Crystallogr.</em> <strong>1996</strong>, <em>52</em>, 770–781; H. Boysen, <em>Z. Kristallogr.</em> <strong>2003</strong>, <em>218</em>, 123–131].<br><br>JANA2006, one of the standard programs in powder and single-crystal diffractometry, readily calculates the probability-density function (PDF) in 2D and 3D. However, it does only allow for derivation of the resulting one-particle potential (OPP) in 1D, <i>i.e.</i>, along a pathway within a 2D section. This problem is overcome by CalcOPP-3D, which reads temporary output from JANA2006 and calculates a 3D OPP map in a format fit for visualization using VESTA.<br>