Molecular Complexity by Spectroscopy

Experimental Assembly Theory using NMR, IR, and MS/MS measurements.

This project asks a simple experimental question: can molecular complexity be measured directly from spectra, without first solving the full molecular structure?

The work uses Assembly Theory to connect molecular structure, spectroscopic observables, and the probability that a molecule was generated by an unconstrained process. The informal “alien detector” nickname is memorable, but the stronger framing is broader: a spectroscopy-led way to quantify molecular complexity in unknown chemical samples.

Measurement Scheme

Three complementary experimental readouts, NMR, IR, and MS/MS, are used to estimate molecular assembly complexity.

NMR reports on the number and type of distinct atomic environments. IR provides a compact fingerprint of functional group and vibrational diversity. MS/MS gives a fragmentation graph that can be compared with assembly pathways. Together these measurements make complexity a practical experimental observable.

Results

Experimental estimates correlate with computed molecular assembly across chemically diverse samples.

The key technical result is that different instruments can converge on a shared complexity estimate. That matters because it makes the method robust to the constraints of real samples and real instruments.

Why It Matters

An experimental complexity metric is useful in astrobiology, origins-of-life chemistry, reaction discovery, and automated sample triage. It gives autonomous platforms a measurable target that is not just yield, purity, or structural identity.

References