File Name : figure s1.tif

Caption : <b>fig. s1</b> (a) scheme of diamond anvil cell (dac). (b) photograph of sample during the under-pressure experiment. (c) scheme of membrane, exterior of dac. 

File Name : figure s2.tif

Caption : <b>fig. s2</b> peak surface integration: s2 (bleu: 520 to 540 nm), s1 (green: 540 to 560 nm).