TY - JOUR
T1 - Photoisomerization of azobenzene dendrimer monolayer investigated by Maxwell displacement current technique
AU - Shimura, Daisuke
AU - Manaka, Takaaki
AU - Nakamoto, Masayuki
AU - Zhao, Wei
AU - Majima, Yutaka
AU - Iwamoto, Mitsumasa
AU - Yokoyama, Shiyoshi
AU - Kubota, Tohru
AU - Mashiko, Shinro
PY - 2001/12
Y1 - 2001/12
N2 - Photoisomerization in monolayers of a novel azobenzene compound, azobenzene dendrimer, was investigated for the first time by means of the absorption spectrum and Maxwell displacement current (MDC) technique. According to the absorption spectrum, trans-to-cis conversion ratio was estimated to be approximately 10% for the third generation of azobenzene dendrimer deposited onto a glass substrate. Temperature-dependent induced charge with trans-cis isomerization was also measured by means of MDC technique, and we found that the thermal isomerization process must be taken into account for theoretical analysis of trans-to-cis photoisomerization. The temperature dependence was theoretically treated in terms of the three-state model that takes into account the stimulated thermal isomerization. As a result, we could obtain a ground state energy barrier of 0.93 eV in cis-to-trans isomerization for the first-generation of the azobenzene dendrimer (AZ-G1), and the value is in good agreement with the previous results obtained from the molecular orbital (MO) calculation which suggests that thermal cis-to-trans isomerization in AZ-G1 passes through the inversion process.
AB - Photoisomerization in monolayers of a novel azobenzene compound, azobenzene dendrimer, was investigated for the first time by means of the absorption spectrum and Maxwell displacement current (MDC) technique. According to the absorption spectrum, trans-to-cis conversion ratio was estimated to be approximately 10% for the third generation of azobenzene dendrimer deposited onto a glass substrate. Temperature-dependent induced charge with trans-cis isomerization was also measured by means of MDC technique, and we found that the thermal isomerization process must be taken into account for theoretical analysis of trans-to-cis photoisomerization. The temperature dependence was theoretically treated in terms of the three-state model that takes into account the stimulated thermal isomerization. As a result, we could obtain a ground state energy barrier of 0.93 eV in cis-to-trans isomerization for the first-generation of the azobenzene dendrimer (AZ-G1), and the value is in good agreement with the previous results obtained from the molecular orbital (MO) calculation which suggests that thermal cis-to-trans isomerization in AZ-G1 passes through the inversion process.
UR - http://www.scopus.com/inward/record.url?scp=0035713077&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035713077&partnerID=8YFLogxK
U2 - 10.1143/jjap.40.7085
DO - 10.1143/jjap.40.7085
M3 - Article
AN - SCOPUS:0035713077
VL - 40
SP - 7085
EP - 7090
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 12
ER -