Abstract
Molecular vibration of several modes in blue-phase polydiacetylene-3-butoxycarbonylmethylurethane (PDA-3BCMU) was real-time observed by 5-fs pump-probe measurement. The contribution of the vibrational wave packets in the ground state and in the excited state in the signal were separated by multichannel measurement. The stretching mode in the ground state starts to oscillate -out-of-phase with the stretching mode. The structure of PDA-3BCMU in the geometrically relaxed state is not pure butatriene type but more like acetylene type. The frequencies of and stretching modes there were determined by singular value decomposition method to be and , respectively. The double and triple bond stretching frequencies in the ground state are and , respectively.
1 More- Received 11 May 2004
DOI:https://doi.org/10.1103/PhysRevB.70.214301
©2004 American Physical Society