EP 0503748 A3 19930428 - METHOD AND APPARATUS FOR GENERATING IONS, SPECIALLY FOR A MASS SPECTROMETER SUCH AS A TIME-OF-FLIGHT MASS SPECTROMETER, FROM THERMALLY INSTABLE, NON-VOLATILE, LARGE MOLECULES
Title (en)
METHOD AND APPARATUS FOR GENERATING IONS, SPECIALLY FOR A MASS SPECTROMETER SUCH AS A TIME-OF-FLIGHT MASS SPECTROMETER, FROM THERMALLY INSTABLE, NON-VOLATILE, LARGE MOLECULES
Publication
Application
Priority
- DE 4108462 A 19910313
- DE 4108463 A 19910313
Abstract (en)
[origin: EP0503748A2] A method for generating ions, especially for a mass spectrometer, such as a time-of-flight mass spectrometer, from thermally unstable, non-volatile large molecules, in which a sample substance having the molecules is subjected to energy pulses by means of which molecules are released from the sample substance, and in which the released molecules are taken by a jet of a carrier gas and are cooled during its expansion as well as subsequently being ionised in an ionisation space, characterised in that the molecules are ionised by electron impact; in that the radiation density of the electrons which are used for the ionisation is selected such that a potential trough is produced, at the focus of the electron beam, whose depth is greater than the translation energy of the molecule ions in the carrier gas flow; in that the molecule ions generated by the electron impact ionisation are collected in the potential trough in each case for a specific period of time; and in that the molecule ions which are in each case collected in the potential trough are accelerated in a pulsed manner out of the ionisation chamber, and an apparatus especially for carrying out this method. <IMAGE>
IPC 1-7
IPC 8 full level
H01J 49/04 (2006.01); H01J 49/14 (2006.01); H01J 49/16 (2006.01); H01J 49/40 (2006.01)
CPC (source: EP US)
H01J 49/0463 (2013.01 - EP US); H01J 49/147 (2013.01 - EP US)
Citation (search report)
- APPLIED PHYSICS B. PHOTOPHYSICS AND CHEMISTRY, Band B41, Nr. 6, Dezember 1990, Seiten 395-403, Heidelberg, DE; G. MEIJER et al.: "Laser desorption jet-cooling of organic molecules"
- ANALYTICAL INSTRUMENTATION, Band 16, Nr. 1, 1987, Seiten 93-115, New York, US; J.K. OLTHOFF et al.: "Modification of Wiley-McLaren TOF analysers for laser desorption"
- PHYSICAL REVIEW, B. CONDENSED MATTER, Band 38, Nr. 5, 15. August 1988, Seiten 3517-3520, New York, US; C.W.S. CONOVER et al.: "Laser vaporisation of solids into an inert gas: a measure of high-temperature cluster stability"
- REVIEW OF SCIENTIFIC INSTRUMENTS, Band 59, Nr. 4, April 1988, Seiten 557-561, New York, US; L. LI et al.: "Pulsed laser desorption method for volatilizing thermally labile molecules for supersonic jet spectroscopy"
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
EP 0503748 A2 19920916; EP 0503748 A3 19930428; EP 0503748 B1 19961211; DE 4108462 A1 19920917; DE 4108462 C2 19941013; DE 59207642 D1 19970123; EP 0669638 A1 19950830; US 5294797 A 19940315
DOCDB simple family (application)
EP 92250055 A 19920307; DE 4108462 A 19910313; DE 59207642 T 19920307; EP 95104288 A 19920307; US 84988692 A 19920312