Polymer Soft-Landing Isolation of Acetylene on Polystyrene and Poly(vinylpyridine): A Novel Approach to Probing Hydrogen Bonding in Polymers.

Hydrogen-bonded complexes of acetylene (Ac) with the polymers polystyrene (PS), poly(4-vinylpyridine) (P4VP), and poly(2-vinylpyridine) (P2VP) have been characterized for the first time at 16 K in a "polymer soft-landing isolation" experiment which is being pioneered in our research laboratory. In particular, changes in vibrational modes of Ac provide ample evidence for hydrogen-bonded complexes between Ac and the phenyl groups of PS or the pyridyl groups of P4VP and P2VP. With PS, the proton on the top Ac molecule of the classic T-shaped Ac dimer interacts with the π cloud of the benzene (Bz) ring to form a C-H---π interaction, while the π cloud of the lower Ac forms a second C-H---π interaction with a proton on the Bz ring.

Matrix and polymer soft-landing isolation of selected acids with pyridine and poly(4-vinylpyridine): a comparative infrared spectroscopic study of hydrogen bonding.

Hydrogen bonding plays a key role in the formation of nanostructures, as it is the "glue" between layers that are built by the layer-by-layer technique. Poly(4-vinylpyridine) (PVP) is one of the most commonly used polymers in these sandwich-structured films, often in conjunction with poly(carboxylic acid)s such as poly(acrylic acid) in the PVP/PAA interpolymer complex. In addition, PVP is commonly used as a polymer matrix for embedding semiconductor nanoparticles.

Pentachlorocyclopropane/base complexes: matrix isolation infrared spectroscopic and density functional study of C-H- - -N hydrogen bonds.

Hydrogen-bonded complexes of pentachlorocyclopropane with the bases acetonitrile, ammonia, monomethylamine, and dimethylamine have been isolated and characterized for the first time in argon matrices at 16 K. Coordination of the proton of pentachlorocyclopropane (Pccp) to the electron donor (N) of the base was evidenced by red shifts of the CH stretching mode. These shifts, which range from 22 to 170 cm(-1), increase in the order CH3CN, NH3, (CH3)NH2, and (CH3)2NH.