Updated Atom/Functional Group and Atom_Code Volume Additivity Parameters for the Calculation of Crystal Densities of Single Molecules, Organic Salts, and Multi‐Fragment Materials Containing H, C, B, N, O, F, S, P, Cl, Br, and I

Data for crystal structures with ≤10 fragments per asymmetric unit from the Cambridge Structural Database were used to update and extend our previously described databases. Atom and functional group volumes and densities were determined for organic compounds with the elements H, C, B, N, O, F, P, S, Cl, Br, I, and halide anions. The datasets included organic ions and multi-fragment structures. Linear and nonlinear volumes and linear densities were determined for 109 predefined atoms/functional groups from ∼41000 crystal structure data. An updated volume database for atom_codes, which are automatically defined by the atoms and their connections in a dataset, was determined in separate calculations with 2805 atom_codes defined for ∼48000 structures. The atom_code extension to 6-coordinate C and B allowed carboranes to be modeled. The average percent difference between the observed and calculated densities is about 2%.