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Mass Spectroscopy Analysis

Important information for this page

This page contains a collection of information how to reference analytical data. We provide this page to describe the preferred formatting of analytical evaluations in the Chemotion repository. The given preferences follow standards of journals/publishers and other stakeholders wherever we could find them. Currently, in particular the format of the metadata of the analytical data (everything before "=") is not reviewed critically. If you have suggestions and comments: please let us know or provide your ideas via the issue tracking option. https://github.com/ComPlat/chemotion_saurus/issues Updated: 01.03.2024

Mass spectrometry data​

  1. Please give mass spectra in the form of the following examples. Important conventions are the listing of signals with their intensity (in round brackets) and the assignment of fragments to the corresponding sum formula [in squared brackets].

EI-MS

  • MS (EI, 70 eV, 70 °C): m/z (%) = 278 (72) [M]+, 221 (100), 147 (31), 115 (15), 103 (23); HRMS–EI (m/z): [M]+ calcd for C15H18OS2, 278.0794; found, 278.0795.
  • MS (EI, 70 eV, 70 °C): m/z (%) = 278/280 (72/72) [M]+, 221/223 (100/100), 103 (23).

ESI-MS

Please mention the mode as well as the solvent used.

  • MS (ESI+, CH2Cl2) m/z (%) : 337 (53) [M+Na]+, 305 (60) [M+H]+, 290 (11), 282 (16), 275 (17), 274 (100), 230 (10), 165 (10), 150 (12), 130 (34), 120 (10). HRMS (ESI+, CH2Cl2) m/z (%) calcd for C20H21N2O+ 305.1648, found 305.1644.
  • MS (ESI-, MeCN) m/z (%) : 162 (40) [M-H]-, 140 (22), 119 (100), 56 (38).
  1. Please ensure that the peak with the highest detected molecular mass belongs to your molecule (either as fragment if the molecule peak is not found, or as part of a formed complex/dimer or similar). If there are signals with a higher mass than your product, please explain these masses and give this explanation after the signal in the signal list. Please indicate additional signals in the form of either:
  • Impurities: explanation
  • Reference: explanation
  1. Please group the peaks according to signals that refer to one molecule fragment (all peaks belonging to an isotopic pattern form one signal group). Please start the listing of signals with the highest detected mass and finish with the lowest.
  2. Within one signal, please list the peaks from low to high m/z.
  3. Please give isotope patterns for Cl- and Br-containing compounds
  4. Please remove naturally occurring isotopes.
  5. HRMS

Examples for Organic chemistry

In case [M]+ or [M+H]+ is given, please make sure to calculate the theoretical mass for the cationic species (electron removed).

  • HRMS (ESI-TOF, MeCN): m/z = calcd for C13H17NO3Na [M+Na]+ 258.1106; found 258.1104.
  • HRMS (FAB, matrix NBA): m/z = calcd for C13H18NO3 [M+H]+: 236.1287; found: 236.1290.
  • HRMS (ESI+, CH2Cl2): m/z = calcd for C25H31N2O2+ [M+H]+: 391.2380; found 391.2377.
  • HRMS (ESI-, MeCN): m/z = calcd for C9H6O3- [M-H]-: 163.0401; found 163.0404.

Examples for Inorganic chemistry In case [M]+ or [M+H]+ is given, please make sure to calculate the theoretical mass for the cationic species (electron removed).

  • HRMS (ESI+, MeCN): m/z (%) = 663.24608 (100), 664.24910 (37), 665.24508 (48), 666.24762 (17), 667.25040 (3). m/z (calc) = 663.24630 [12C321H4063Cu14N816O4+] (100), 664.24966 [12C3113C1H4063Cu14N816O4+] (35), 665.24449 [12C321H4065Cu14N816O4+] (45), 666.24785 [12C3113C1H4065Cu14N816O4+] (15), 667.25120 [12C3013C21H4065Cu14N816O4+] (3).