Volume 217, 2019

Photodetachment and photoreactions of substituted naphthalene anions in a tandem ion mobility spectrometer

Abstract

Substituted naphthalene anions (deprotonated 2-naphthol and 6-hydroxy-2-naphthoic acid) are spectroscopically probed in a tandem drift tube ion mobility spectrometer (IMS). Target anions are selected according to their drift speed through nitrogen buffer gas in the first IMS stage before being exposed to a pulse of tunable light that induces either photodissociation or electron photodetachment, which is conveniently monitored by scavenging the detached electrons with trace SF6 in the buffer gas. The photodetachment action spectrum of the 2-naphtholate anion exhibits a band system spanning 380–460 nm with a prominent series of peaks spaced by 440 cm−1, commencing at 458.5 nm, and a set of weaker peaks near the electron detachment threshold corresponding to transitions to dipole-bound states. The two deprotomers of 6-hydroxy-2-naphthoic acid are separated and spectroscopically probed independently. The molecular anion formed from deprotonation of the hydroxy group gives rise to a photodetachment action spectrum similar to that of the 2-naphtholate anion with an onset at 470 nm and a maximum at 420 nm. Near the threshold, the photoreaction with SF6 is observed with displacement of an OH group by an F atom. In contrast, the anion formed from deprotonation of the carboxylic acid group gives rise to a photodissociation action spectrum, recorded on the CO2 loss channel, lying at much shorter wavelengths with an onset at 360 nm and maximum photoresponse at 325 nm.

Graphical abstract: Photodetachment and photoreactions of substituted naphthalene anions in a tandem ion mobility spectrometer

Associated articles

Supplementary files

Article information

Article type
Paper
Submitted
30 nov 2018
Accepted
10 jan 2019
First published
10 jan 2019

Faraday Discuss., 2019,217, 34-46

Photodetachment and photoreactions of substituted naphthalene anions in a tandem ion mobility spectrometer

J. N. Bull, J. T. Buntine, M. S. Scholz, E. Carrascosa, L. Giacomozzi, M. H. Stockett and E. J. Bieske, Faraday Discuss., 2019, 217, 34 DOI: 10.1039/C8FD00217G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements