title: Spatially resolved analysis of short-range structure perturbations in a plastically bent molecular crystal.
abstract: The exceptional mechanical flexibility observed with certain organic crystals defies the common perception of single crystals as brittle objects. Here, we describe the morphostructural consequences of plastic deformation in crystals of hexachlorobenzene that can be bent mechanically at multiple locations to 360° with retention of macroscopic integrity. This extraordinary plasticity proceeds by segregation of the bent section into flexible layers that slide on top of each other, thereby generating domains with slightly different lattice orientations. Microscopic, spectroscopic and diffraction analyses of the bent crystal showed that the preservation of crystal integrity when stress is applied on the (001) face requires sliding of layers by breaking and re-formation of halogen-halogen interactions. Application of stress on the (100) face, in the direction where π···π interactions dominate the packing, leads to immediate crystal disintegration. Within a broader perspective, this study highlights the yet unrecognized extraordinary malleability of molecular crystals with strongly anisotropic supramolecular interactions.
authors.affiliation: New York University Abu Dhabi, PO Box 129188, Abu Dhabi, United Arab Emirates.
authors.forename: Manas K
authors.initials: MK
authors.lastname: Panda
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur Campus, Mohanpur 741 246, India.
authors.forename: Soumyajit
authors.initials: S
authors.lastname: Ghosh
authors.affiliation: Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5198, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yasuda
authors.affiliation: Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5198, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Moriwaki
authors.affiliation: Department of Physical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur Campus, Mohanpur 741 252, India.
authors.forename: Goutam Dev
authors.initials: GD
authors.lastname: Mukherjee
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur Campus, Mohanpur 741 246, India.
authors.forename: C Malla
authors.initials: CM
authors.lastname: Reddy
authors.affiliation: New York University Abu Dhabi, PO Box 129188, Abu Dhabi, United Arab Emirates.
authors.forename: Panče
authors.initials: P
authors.lastname: Naumov