Converting IR Spectroscopy to Music

A New Type of Transformation

IR spectroscopy gives us a set of absorption bands in 1/cm units, but what if they could be transformed into distinct frequencies for each peak? Doing so could result in a set of notes that could then be used to make music! This was what happened when a group of students led projects in a published article for the Journal of Chemical Education, creating sounds from IR spectroscopy data. To do this, the students first recorded the IR spectroscopy data of various compounds, then multiplied the key absorption bands (in reciprocal centimeters) by the speed of light to obtain frequency. This can be explained through the equation ν = ν1 × c, where v is frequency, v1 is the wavenumber in reciprocal centimeters, and c is the speed of light. This value was then divided by a common coefficient to bring this frequency into the human auditory range, which could then be related to notes on a scale. These notes were then used to make compositions that could represent the molecule, ranging from carbon dioxide with just two notes (B4 and C#3), to dibenzeacetone with eight notes (G5, E4, D#4, C#4, B3, G3, D#3, and C#3). Have a listen below!