A Raman spectral study is reported for a polydiacetylene crystal with substituent group -(CH2)4OCONHC6H5. At low temperatures (<100K) or high pressures (>1.5kbar) a phase change occurs accompanied by changes in the electronic structure of the polymer backbone. The Raman evidence suggests that the high temperature phase is best described with a butatriene bonding sequence [opening parenthesis with horizontal barRC=C=C=CRclosing parenthesis with horizontal bar] while the low temperature (or high pressure) phase is best described with an acetylene bonding sequence [opening parenthesis with double horizontal barRC-C≡C-CRclosing parenthesis with double horizontal barn].
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy
- Physical and Theoretical Chemistry