Photodissociation study of spatially oriented (R)-3-bromocamphor by the hexapole state selector

Abstract

A photodissociation experiment of (R)-3-bromocamphor was carried out by the hexapole orientation technique by (2 + 1) REMPI detection at about 234 nm. The atomic bromine products in excited state (Br ²P_1/2) and in ground state (Br ²P_3/2) were observed by the velocity map imaging. The anisotropy parameters of Br (²P_1/2) and Br (²P_3/2) were obtained as 0.75 ± 0.04 and 0.48 ± 0.03, respectively. In addition, we also successfully controlled (R)-3-bromocamphor, the bulky and asymmetric bio-molecule’s, spatial orientation using the electrostatic hexapole. The orientational distribution was derived and its orientation efficiency was estimated as |<cos θ>|=0.35. We carried out a slice imaging experiment with the spatially oriented parent molecules to study the photodissociation dynamics of (R)-3-bromocamphor. The angular analysis of the obtained slice images suggests fast axial recoiling of the bromine atomic fragments and comparable contributions from the multiple upper states involved in A-band excitation, which results in the relatively isotropic angular distributions.

GRAPHICAL ABSTRACT

KEYWORDS:

• Hexapole
• orientation
• ion image
• bromocamphor
• photodissociation

Acknowledgement

The author H.-P. C. thanks all co-workers for their support. This work is supported by the Ministry of Science and Technology of Taiwan, Republic of China, under Contract No. NSC 109-2113-M-002 -002. T. K. thanks National Taiwan University for providing him a visiting professorship to carry out this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Ministry of Science and Technology, Taiwan: [Grant Number NSC 109-2113-M-002-002 -].