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- Posts: 8
- Joined: Thu Jul 20, 2006 12:07 pm
Dear all,
I was wondering if anyone has experience with the measuring or prediction of ionization cross sections of larger molecules. I need these values for a wide range of substances like PAHs, pyridines, methoxyphenols, straight-chain aliphatics, furans, fatty acids, etc.
The literature lacks experimental data for the majority of these component classes. Prediction models assuming additivity of atomic ionization cross sections are easily applied, but such empirical models are not very reliable. Also, in at least one of these models, the positive effect of pi-bond formation on ionization probability of aromatics is not included (information on this issue in particular is desired). More robust models exist, but these are developed with the goal of determining ionization cross sections of small molecular radicals.
Can anyone help me on the way (again - see thread 'GC/MS response factors')
Regards, Joeri
I was wondering if anyone has experience with the measuring or prediction of ionization cross sections of larger molecules. I need these values for a wide range of substances like PAHs, pyridines, methoxyphenols, straight-chain aliphatics, furans, fatty acids, etc.
The literature lacks experimental data for the majority of these component classes. Prediction models assuming additivity of atomic ionization cross sections are easily applied, but such empirical models are not very reliable. Also, in at least one of these models, the positive effect of pi-bond formation on ionization probability of aromatics is not included (information on this issue in particular is desired). More robust models exist, but these are developed with the goal of determining ionization cross sections of small molecular radicals.
Can anyone help me on the way (again - see thread 'GC/MS response factors')
Regards, Joeri
