Ken Wrote: Greetings, I'm looking for x-ray absorbtion coefficients for SiO2 (LTO) and SiNx (PECVD) and Aluminum. I'm specifically interested in values corresponding to wavelengths of 2-10 Angstroms, but values at other wavelengths would be useful as well. Thanks for any info, Ken ---------------------------------- Ken, You are in LUCK, because MOXTEK has developed for commercial and scientific use a program called MOXGRAF which calculates the x-ray optical constants for any compound you want to type in for the energy range 10 eV to 30 keV, in eV or angstoms, and not only that, but will calculate transmission, reflection beta, delta, f1, f2, and just about anything else and PLOT it in full color for your entertainment and edification. And best of all it costs not $1000, not $100, but for the low low price of FREE! The bad news is that no one here has been motivated to put it on our website, so you have to request it. And the policy for requesting it is to FAX the request, not to e-mail it. The FAX number is 801-221-1121. best regards mark Mark W. Lund, PhD Director >> Soft X-ray Web page http://www.moxtek.com<< MOXTEK, Inc. 452 West 1260 North Orem UT 84057 801-225-0930 FAX 801-221-1121 lundm@xray.byu.edu "The state is good at simple tasks, like killing people and seizing their wealth. It has far more trouble reaching inside individuals and making them good." Doug Bandow