Variable-temperature neutron diffraction studies of the short, strong N...O hydrogen bonds in the 1:2 co-crystal of benzene-1,2,4,5-tetracarboxylic acid and 4,4'-bipyridyl.
The 1:2 adduct of benzene-1,2,4,5-tetracarboxylic acid and 4,4'-bipyridyl at 100 K has been studied by single-crystal neutron diffraction at 20, 200 and 296 K. The structure contains two short, strong N...O hydrogen bonds: one O-H...N hydrogen bond [O...N 2.6104 (17) A at 20 K] and one short N-H...O hydrogen bond [N...O 2.5220 (17) A at 20 K]. The N-H distance in the N-H...O hydrogen bond changes from 1.207 (3) A at 20 K to 1.302 (4) A at 296 K and the N...O distance increases to 2.5315 (16) A at 296 K. At 200 K the H atom lies in an intermediate position 1.251 (6) A from the N atom with an N...O separation of 2.520 (4) A. The O-H...N hydrogen bond, on the other hand, does not change with temperature.
Cowan
John A
JA
Institut Laue-Langevin, 6 rue Jules Horowitz, BP156, 38042 Grenoble 9, France. jacowan@anl.gov
Howard
Judith A K
JA
McIntyre
Garry J
GJ
Lo
Samuel M-F
SM
Williams
Ian D
ID
D003461:Crystallography; D005583:Fourier Analysis; D006860:Hydrogen Bonding; D015394:Molecular Structure; D033363:Neutron Diffraction; D009502:Neutrons; D009584:Nitrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry; D011522:Protons; D012984:Software; D013696:Temperature; D014965:X-Rays
D011522:Protons; D009584:Nitrogen; D010100:Oxygen