The structural and dynamic properties of 1-bromodecane in urea inclusion compounds investigated by solid-state H-1, C-13 and H-2 NMR spectroscopy

作者：Yang Xiaorong^*; Mueller Klaus

来源：Magnetic Resonance in Chemistry, 2011, 49(8): 514-522.

DOI：10.1002/mrc.2785

• solid-state NMR
• H-1
• C-13 and H-2
• structure and dynamics
• 1-bromodecane
• urea inclusion compounds

For asymmetric guest molecules in urea, the end-groups of two adjacent guest molecules may arrange in three different ways: head-head, head-tail and tail-tail. Solid-state H-1 and C-13 NMR spectroscopy is used to study the structural properties of 1-bromodecane in urea. It is found that the end groups of the guest molecules are randomly arranged. The dynamic characteristics of 1-bromodecane in urea inclusion compounds are probed by variable-temperature solid-state H-2 NMR spectroscopy (line shapes, spin-spin relaxation: T-2, spin-lattice relaxation: T-1Z and T-1Q) between 120 K and room temperature. The comparison between the simulation and experimental data shows that the dynamic properties of the guest molecules can be described in a quantitative way using a non-degenerate three-site jump process in the low-temperature phase and a degenerate three-site jump in the high-temperature phase, in combination with the small-angle wobbling motion. The kinetic parameters can be derived from the simulation.

• 出版日期2011-8