Abstract
We have developed a method of ionization (liquid ionization method) for organic compounds in the lipuid phase at atmospheric pressure. Major ions produced by this method are MmH+ ions which can be measured at pinhole potential of less than 20 V. The number m is 1 and 2 for most of the compounds measured, even for less volatile compounds like amino acids. Several fragment ions measured at pinhole potential of around 50V are similar to those obtained by CI and the ions measured at higher pinhole potential become partly similar to those obtained by EI. Therefore, the mass spectrum obtained by this method is quite useful for determining the structure of a compound.
Mass spectra of a synthetic compound, a kind of oligomer, were measured by this method and its molecular weight and the structure of the compound were determined. This is the largest compound (M.W.=536) we have measured so far.
