To get property data from SciFinder, use "Explore Substances" and then click "Experimental Properties" to the bottom left of the structure to go right to the properties or "Substance Details" above the structure and scroll down.
Contains experimentally validated substance information from the chemical literature and patents. Especially strong for finding reactions and property data of organic, inorganic, and organometallic substances. Has information formerly in Beilstein and Gmelin Handbooks.
Contains MS (electron impact), FT-IR, 1H NMR, 13C NMR, Raman, and ESR spectral data. Over 34,000 compounds total. Maintained by the Japanese National Institute of Advanced Industrial Science and Technology (AIST). FAQ is here.
Reaxys has superb spectral search capabilities. Click "exists" next to Spectra in the "Properties (Advanced)" box to only retrieve records with spectral data. See the Reaxys libguide (forthcoming) for details.