The design and construction of a lithium ion attachment mass spectrometer t
hat is used to study the occurrence of free radical intermediates and molec
ular and atomic species (which are not found under ordinary conditions) on
a real-time basis in the gas phase are described. The newly developed devic
e exhibits several advantages over conventional mass spectrometers. The per
formance of this equipment was extensively tested and optimized, and experi
mental tests show that the efficiency and sensitivity of the instrument are
moderately high. The main applications and possible future perspectives of
this approach are briefly reviewed. (C) 2001 American Institute of Physics
.