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Title: Laser desorption mass spectrometry of rubrene and photodissociation of its cation
Laser desorption mass spectrometry was employed to study rubrene using three different sample preparation methods. Pressed-pellet and films drop-cast from solution were investigated with a laser-desorption time-of-flight spectrometer. Jet-cooled rubrene cations were produced in a supersonic molecular beam by laser desorption from a film-coated metal rod and detected with time-of-flight mass spectrometry. The films for this process were produced by vacuum sublimation of powder samples. The mass spectra from each of these samples contained the parent molecular ion and fragments resulting from phenyl ring elimination - a pattern similar to that produced by electron impact ionization. The amount of fragmentation varied with sample preparation and desorption laser wavelength. The rubrene cation was mass selected and studied with UV laser photodissociation at 355 nm. The resulting fragmentation mass spectrum indicated the loss of one or two phenyl groups, but no more than this. Computational studies of the ion energetics were used to investigate the stable fragment ion structures and understand the energetics of the dissociation process.  more » « less
Award ID(s):
2154011
PAR ID:
10519284
Author(s) / Creator(s):
; ;
Editor(s):
Laskin, Julia
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
International Journal of Mass Spectrometry
Volume:
503
Issue:
C
ISSN:
1387-3806
Page Range / eLocation ID:
117280
Subject(s) / Keyword(s):
laser desorption mass spectrometry laser photodissociation computational chemistry molecular beams
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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