Evolved gas analysis–ion attachment mass spectrometric observation of Mn(CO)_5 and Mn_2(CO)_9 radicals produced by Mn_2(CO)_(10) pyrolysis

摘要

Evolved gas analysis–ion-attachment mass spectrometry (EGA–IAMS) indicates that Mn(CO)_5 and Mn_2(CO)_9 free radicals are produced in the gas phase by pyrolysis of Mn_2(CO)10 in an infrared image furnace. The Li~+-adduct mass spectra of the pyrolysis products contained peaks at m/z 202 and 36_9 for Mn(CO)_5Li~+ and Mn_2(CO)_9Li~+, respectively, providing direct evidence that d-metal complex radicals were formed in the furnace. We studied the effect of temperature on the rate of production of the radicals, and confirmed the presence of the compounds Mn(CO)_5 and Mn_2(CO)_9, which were reported in earlier studies based on electron-impact mass spectrometry, electron spin resonance spectroscopy, and Fourier transform infrared spectroscopy.