Octachloropropane or perchloropropane is the chemical compound with elemental formula and structural formula . Its molecule has a simple chain of three carbon atoms connected by single bonds, with chlorine atoms filling their remaining bonds. It is a chlorocarbon, specifically the third simplest perchloroalkane. It can be described as a derivative of propane , with all hydrogen atoms replaced by chlorine. Octachlorpropane is a clear white crystalline solid at room temperature, with hexagonal crystal structure. It is easily deformed by mechanical stress, without losing its crystal structure—like a metal. History Synthesis and characterization of octachloropropane was reported in 1875 by Krafft and Merz. Its remarkable crystal growth and deformation properties were noted by McCrone in 1949. Its use as a model for crystal deformation of minerals was pioneered by Win D. Means, Marc W. Jessel and others in the 1980s. Production Octachloropropane can be obtained by reacting partially chlorinated propane with iodine trichloride (as in the original synthesis by Krafft and Merz), or with chlorine at high pressure or with activation by light. The temperature must be close to but below 200 °C, since at higher temperatures further reaction with chlorine gives carbon tetrachloride and hexachloroethane instead. Chemistry Octachloropropane treated with aluminum in diethyl ether affords several unsaturated perchlorocarbons, by way of hexachloropropene (, ). For instance, + 2/3 2/3 + 2 + 4/3 4/3 + (three isomers) 2 + 2 2 + (two isomers) The products were identified as α-: colorless, m. p. 148 °C. β-: red, m. p. 155 °C with conjectured structures or , and α-: b. p. 105-110 °C at 0.1 torr. β-: m. p. 71 °C. γ-: m. p. 183 °C. which were claimed to be cis/trans isomers and atropisomers of (octachloro(1,3,5)hexatriene). Applications Crystalline plasticity model Octacholopropane is used by geologists and metallurgists as a model to study the plastic deformation of crystalline minerals and rocks under stress. The large individual crystalline grains (0.1-1.0 mm diameter) are distinguishable with a polarized light microscope at moderate magnification, and generally retain their size and approximate aspect ratio as the material undergoes shear strain. The grains will spontaneously arise from the quenched solid, in minutes or hours, even at room temperature. The material's flow driven by stress can be followed by embedding in it small amounts of fine inert particles, such as grit 1000 abrasives; the particles apparently do not affect the grain evolution and deformation. Camphor (with