IR and UV Spectroscopy of Vapor-Phase Jet-Cooled Ionic Liquid [emim]+[Tf2N]-: Ion Pair Structure and Photodissociation Dynamics

被引：49

作者：

Cooper, Russell ^{[1
]}

Zolot, Alexander M. ^{[1
,2
]}

Boatz, Jerry A. ^{[3
]}

Sporleder, David P. ^{[1
]}

Stearns, Jaime A. ^{[1
]}

机构：

[1] Air Force Res Lab, Space Vehicles Directorate, Kirtland Afb, NM 87117 USA

[2] Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA

[3] Air Force Res Lab, Aerosp Syst Directorate, Edwards Afb, CA 93524 USA

来源：

JOURNAL OF PHYSICAL CHEMISTRY A | 2013年 / 117卷 / 47期

关键词：

CORRELATED MOLECULAR CALCULATIONS; ISOLATION FTIR SPECTROSCOPY; GAUSSIAN-BASIS SETS; CATION-ANION; CONFORMATIONAL ISOMERIZATION; INFRARED-SPECTROSCOPY; GAS-PHASE; IONIZATION; PHOTOIONIZATION; VAPORIZATION;

D O I：

10.1021/jp409670n

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Small gas-phase clusters (ion pairs) of the ionic liquid [emim](+)[Tf2N](-) have been generated in a supersonic expansion. Clusters are investigated via UV photofragmentation and time-of-flight mass spectrometry. Spectra between 42 000 and 45 000 cm(-1) reveal dynamical branching between direct dissociation of the ion pair to the cation and anion and to radical species. The IR spectrum between 2800 and 3200 cm(-1) was measured by action spectroscopy. Multiple conformations of the ion pair are found to be present in the molecular beam, leading to broad spectral features, further complicated by hydrogen bonding and Fermi resonances. The measured and theoretical spectra compare well, and the jet-cooled ion pair structures present in the molecular beam are strongly hydrogen bonded "stacked" conformers.

引用

页码：12419 / 12428

页数：10

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