Files

Background Correction

An Excel spreadsheet that will calculate a blank-corrected delta value, and the uncertainty in that value due to uncertainties in measurements of both sample and blank. Based on the equations outlined by John Hayes in his Practice and Principles manuscript.

Isotopic Mixing

Similar to the one above, this is an excel spreadsheet that will calculate mixing in a 2-component system where the isotope ratios of each endmember are known. It also calculates the uncertainty in the mixing fraction, which is its real value. Based on the equations outlined by John Hayes in his Practice and Principles manuscript.

Deuterium Enrichments

A common chore in my lab is mixing D₂O and H₂O to produce water of a specified isotopic composition. This Excel spreadsheet does the calculations for you.

Molecular Ion Masses

A very simple Excel table, but one that is very useful for interpreting mass spectra and that I get asked for frequently. It lists the molecular masses of n-alkanes, ketones, alcohols, and fatty acids with varying chain lengths. A second table lists the stable isotope pattern expected for different numbers of carbon atoms. Quick, what is the molecular weight of the TMS derivative of a C32 fatty acid?!