Additional Resources
Below are links to other databases providing optical constants:
Other Optical Constants Databases
https://refractiveindex.info/
https://science.gsfc.nasa.gov/691/cosmicice/constants.html
https://www.astro.uni-jena.de/Laboratory/Database/databases.html
https://www2.mpia-hd.mpg.de/HJPDOC/
https://icedb.strw.leidenuniv.nl/
https://www.sshade.eu/data/experiment/EXPERIMENT_TG_20180503_001
https://www1.univap.br/gaa/nkabs-database/data.htm
http://www.ct.astro.it/lasp/optico.html