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Simmons, R.O. Herwig, Kenneth William 2011-05-17T15:30:51Z 2011-05-17T15:30:51Z 10000-01-01 1988 Single particle kinetic energies of para-hydrogen molecules in para-hydrogen and argon solids have been determined by deep inelastic neutron scattering. The Low Resolution Medium ~nergy Chopper Spectrometer at the Argonne National Laboratory's Intense Pulsed Neutron Source was used to make the measurements at momentum transfers up to 12 A-I. Peaks corresponding to transitions from the molecule's rotational ground state J =0 to the excited states J =1,3, and 5 are observed. The peaks are broadened by the translational center of mass motion of the molecule. A new technique for analyzing data taken with a chopper spectrometer at a pulsed source is implemented. This method employs a numerically determined resolution function. Single particle kinetic energies for solid para-hydrogen are found to be 92.6 ± 1.1, 108.9 ± 4, 129.9 ± 5, and 145.8 ± 4 K for molar volumes of 23.2, 21.26, 19.49, and 18.16 cc/mole respectively. These values are shown to be those of the ground state. This measurement is the first of its kind to span such a large range of molar volumes. The scattering from dilute para-hydrogen molecules embedded in solid argon has also been measured. The single particle kinetic energies are found to be 84.4 iv ± 4, 118.3 ± 5, and 147.6 ± 3 K for a sample at temperatures of 34.2, 54.1, and 74.0 K respectively. These data show the same peak structure as did the solid para-hydrogen experiment. Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-05-17T15:30:51Z No. of bitstreams: 1 1988_herwig.pdf: 3568782 bytes, checksum: 737c010b898b7e5d462c5a5ac499c646 (MD5) Made available in DSpace on 2011-05-17T15:30:51Z (GMT). No. of bitstreams: 1 1988_herwig.pdf: 3568782 bytes, checksum: 737c010b898b7e5d462c5a5ac499c646 (MD5) Previous issue date: 1988 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-05-17T15:30:51Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:13:10-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis Thesis U of I Only 3478218 http://hdl.handle.net/2142/23912 en 1988 Kenneth William Herwig single particle kinetic energies para-hydrogen molecules argon solids deep inelastic neutron scattering Low Resolution Medium Energy Chopper Spectrometer Argonne Intense Pulsed Neutron Source Single particle kinetic energies of para-hydrogen molecules in para-hydrogen and argon solids Dissertation / Thesis text Physics Physics University of Illinois at Urbana-Champaign Dissertation Ph.D.