TY - JOUR
T1 - Structure of the disordered phase of t-butyl cyanide determined using neutron scattering methods
AU - Gane, Patrick A.C.
AU - Leadbetter, Alan J.
AU - Ward, Richard C.
AU - Richardson, Robert M.
AU - Pannetier, Jean
PY - 1982/12/1
Y1 - 1982/12/1
N2 - The structure of the high-temperature phase of t-butyl cyanide has been determined in detail by neutron scattering experiments on single crystals of a fully deuteriated specimen. The structure is tetragonal (P4/n, a = 6.85 Å, c = 6.77 Å) with two molecules per unit cell. Analysis of the intensities of 82 independent reflections show the structure to be disordered, each molecule having one-quarter occupancy of four positions related by π/2 rotations about the four-fold axes. The diffuse scattering intensity shows clearly that local correlations exist which are closely similar in structure to that of the low-temperature monoclinic phase, with a correlation length of ca. 7 Å. New incoherent quasi-elastic scattering measurements provide the basis for a slightly modified analysis of previous results, which are then in complete accord with the above model. The correlation time for rotation of the molecules about their three-fold axes is 10-12s and for the cooperative relaxations among the four local structures the correlation time is ≲10-11 s.
AB - The structure of the high-temperature phase of t-butyl cyanide has been determined in detail by neutron scattering experiments on single crystals of a fully deuteriated specimen. The structure is tetragonal (P4/n, a = 6.85 Å, c = 6.77 Å) with two molecules per unit cell. Analysis of the intensities of 82 independent reflections show the structure to be disordered, each molecule having one-quarter occupancy of four positions related by π/2 rotations about the four-fold axes. The diffuse scattering intensity shows clearly that local correlations exist which are closely similar in structure to that of the low-temperature monoclinic phase, with a correlation length of ca. 7 Å. New incoherent quasi-elastic scattering measurements provide the basis for a slightly modified analysis of previous results, which are then in complete accord with the above model. The correlation time for rotation of the molecules about their three-fold axes is 10-12s and for the cooperative relaxations among the four local structures the correlation time is ≲10-11 s.
UR - http://www.scopus.com/inward/record.url?scp=0001539470&partnerID=8YFLogxK
U2 - 10.1039/F29827800995
DO - 10.1039/F29827800995
M3 - Article (Academic Journal)
AN - SCOPUS:0001539470
SN - 0300-9238
VL - 78
SP - 995
EP - 1008
JO - Journal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Physics
JF - Journal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Physics
IS - 7
ER -