Alkyl-chain Disorder in Tetraisohexylammonium Bromide

Mar 192012
 

Acta Cryst.  (2012), C68, o152-o155.    [ doi:10.1107/S0108270112009377 ]

Tetraisohexylammonium bromide [systematic name: tetrakis(4-methylpentyl)azanium bromide], C24H52N+·Br–, is a powerful structure II clathrate hydrate crystal-growth inhibitor. The crystal structure, in the space group P3221, contains one ammonium cation and one bromide anion in the asymmetric unit, both on general positions. At 100 K, the ammonium cation exhibits one ordered isohexyl chain and three disordered isohexyl chains. At 250 K, all four isohexyl chains are disordered. In an effort to reduce the disorder in the alkyl chains, the crystal was thermally cycled, but the disorder remained, indicating that it is dynamic in nature.

Tetraisohexylammonium Bromide

Tetraisohexylammonium Bromide

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Dr. David R. Allan

Mar 072012
 

Dave is the Principal Beamline Scientist on the small-molecule single-crystal diffraction beamline, I19. Before his appointment at Diamond in 2006, Dave was a lecturer in The School of Physics at The University of Edinburgh and he laterally held an EPSRC Advanced Research Fellowship within The School of Chemistry. Apart from developing the beamline to improve its capabilities for the ever increasing user base, his main research interests involve the high-pressure and low-temperature polymorphism of small-molecule systems and the development of in situ crystal growth techniques. Dave can occasionally been seen around the department, usually on Tuesdays, when he gets the chance to attend the Chem. Cryst. group meetings.

Chiralabs

Mar 072012
 

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