Raman spectra of tridymite modifications: MC, MX-1, and PO-10

In order to facilitate identification of tridymite modifications using micro-Raman spectroscopy, the Raman spectra of synthetic and natural tridymite modifications (MC, MX-1, and PO-10) including low frequency region (ν = 15-200 cm^-1) are measured. The Raman spectrum of MX-1 is reported for the first time. All modifications revealed the characteristic peaks below 150 cm^-1. Using the compiled Raman spectra, tridymite modifications of the reported Raman spectra from meteorites in the literature were identified. It revealed that not only MC, but PO-10 modification exists in the meteorites.