Effects of two types of chemical modifications on photoconducting polymers consisting of polyphenylenevinylene (PPV) derivatives are studied by static and ultrafast transient optical spectroscopy as well as semi-empirical ZINDO calculations. The first type of modification inserts 2,2{prime}-bipyridyl-5-vinylene units (bpy V) in the PPV backbone, and the second type involves metal-chelation with the bpy sites. Photoluminescence and exciton dynamics of polymers 1 and 2 with PV:bpyV ratios of 1 and 3 were examined in solution, and compared to those of the homopolymer, poly(2,5-bis(2{prime}-ethylhexyloxy)-1,4-phenylenevinylene) (BEH-PPV). Similar studies were carried out for several metal-chelated polymers. These results can be explained by changes in {pi}-conjugation throughout the polymer backbone. The attenuation in {pi}-conjugation by the chemical modifications transforms a conducting polymer from one-dimensional semiconductor to molecular aggregates.

Funeral program for Helen Dilworth Adams, born July 8, 1922 and died March 7, 2000. The funeral was held March 11, 2000 at East St. Paul United Methodist Church, officiated by Rev. Barbara Miller. The funeral arrangements were made through Lewis Funeral Home and she was buried in Southern Memorial Park in San Antonio, Texas.

Funeral program for Helen Dilworth Adams, born July 8, 1922 and died March 7, 2000. The funeral was held March 11, 2000at East St. Paul United Methodist Church, officiated by Rev Barbara Miller. Funeral arrangements were made through the Lewis Funeral Home and buried in Southern Memorial Park Cemetery.

Semiweekly newspaper from Pawhuska, Oklahoma that includes local, state, and national news along with advertising.

None