The behavior of pristine single crystal gypsum under tensile loading at a molecular level has been probed in this study based on simulations. Uniaxial stress type tensile loading situations demonstrate anisotropy in response. For both uniaxial and triaxial loading situations, the non-bonded part of the energy governs the response. The response behavior of the tensile stress strain curves in uniaxial and triaxial conditions have been correlated with changes in the molecular structure along with interlayer and intralayer separation distances and layer slippages. (C) 2018 Elsevier Ltd. All rights reserved.