Experimental evidence and theoretical analysis for the chiral symmetry breaking in the growth front of conglomerate crystal phase of 1,1'-binaphthyl.
Chirally asymmetric states, chemical oscillations, propagating chemical waves, and spatial patterns, are examples of far-from-equilibrium self-organization. We have found that the crystal growth front of 1,1(')-binaphthyl shows many of the characteristics of an open system in which chiral symmetry breaking has occurred. From its supercooled molten phase, 1,1(')-binaphthyl crystallizes as a conglomerate of R and S crystals when the temperature is above 145 degrees C. In addition, 1,1(')-binaphthyl in its molten phase is always racemic due to its high racemization rate. Under appropriate conditions, bimodal probability distribution of enantiomeric excess (ee) with maxima around 60% was observed. The ee was mass independent, indicating that the growth front maintains a constant ee. A kinetic model that theoretically analyzes the chiral symmetry breaking transition in the growth front of a conglomerate crystal phase was formulated. Computer simulation of the model reproduced not only the average but also the large variation of the ee observed in crystallization experiments.
Asakura
Kouichi
K
Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1, Hiyoshi, Kohoku, Yokohama 223-8522, Japan. asakura@applc.keio.ac.jp
Plasson
Raphaël
R
Kondepudi
Dilip K
DK
D001703:Biophysics / Q000379:methods*; D002621:Chemistry / Q000379:methods*; D003198:Computer Simulation; D003460:Crystallization; D007700:Kinetics; D008956:Models, Chemical; D009281:Naphthalenes / Q000737:chemistry*; D017711:Nonlinear Dynamics; D011336:Probability; D013237:Stereoisomerism; D013696:Temperature
D009281:Naphthalenes; C412330:1,1'-binaphthyl