title: Prediction of the mechanical behaviour of crystalline solids.
abstract: OBJECTIVE
  To explore the use of crystal inter-planar d-spacings and slip-plane interaction energies for predicting and characterising mechanical properties of crystalline solids.
  
  
  METHODS
  Potential relationships were evaluated between mechanical properties and inter-planar d-spacing, inter-planar interaction energy, and dispersive surface energy as determined using inverse gas chromatography (IGC) for a set of pharmaceutical materials. Inter-planar interaction energies were determined by molecular modelling.
  
  
  RESULTS
  General trends were observed between mechanical properties and the largest inter-planar d-spacing, inter-planar interaction energies, and IGC dispersive surface energy. A number of materials showed significant deviations from general trends. Weak correlations and outliers were rationalised.
  
  
  CONCLUSIONS
  Results suggest that the highest d-spacing of a material could serve as a first-order indicator for ranking mechanical behaviour of pharmaceutical powders, but with some reservation. Inter-planar interaction energy normalised for surface area shows only a weak link with mechanical properties and does not appear to capture essential physics of deformation. A novel framework linking mechanical properties of crystals to the distinct quantities, slip-plane energy barrier and inter-planar interaction (detachment) energy is proposed.
authors.affiliation: Institute of Life Sciences Research, University of Bradford, Bradford, W. Yorkshire BD7 1DP, UK.
authors.forename: Mohammad Hossain
authors.initials: MH
authors.lastname: Shariare
authors.forename: Frank J J
authors.initials: FJ
authors.lastname: Leusen
authors.forename: Marcel
authors.initials: M
authors.lastname: de Matas
authors.forename: Peter
authors.initials: P
authors.lastname: York
authors.forename: Jamshed
authors.initials: J
authors.lastname: Anwar
mesh_terms: D000082:Acetaminophen / Q000737:chemistry; D000420:Albuterol / Q000737:chemistry; D016880:Anisotropy; D002849:Chromatography, Gas; D003460:Crystallization; D007052:Ibuprofen / Q000737:chemistry; D007785:Lactose / Q000737:chemistry; D010316:Particle Size; D011208:Powders / Q000737:chemistry*; D013314:Stress, Mechanical; D013499:Surface Properties; D013816:Thermodynamics
chemical_list: D011208:Powders; D000082:Acetaminophen; D007785:Lactose; D000420:Albuterol; D007052:Ibuprofen