I recently requested a ESI-MS analysis of 2,3,5-tribromothiophene and got this spectrum:
These are the analysis conditions:
- Detector: ESI(+)
- Source Tem: 150
- Capillary voltage: 1.5 kV
- Cone Voltage: 20 V
- Mass range: 200 - 1000
- Flow: 0.2 mL/min
- mobile phase: 0.1% formic acid:acetonitrile (50:50)
The sample was dissolved in methanol. Below is the spectrum of methanol:
The molecular weight of 2,3,5-tribromothiophene is 320.83 g/mol. But why does the base peak occur at m/z=382 and what are higher m/z peaks like m/z=423 and 740? I can't interpret the result at all.