I had recalled it was a phase diagrame a littel later when I posted this. (response to barry that dealt with the same guy I beleive)
http://bbs.msnbc.com/bbs/msnbc-space/posts/fb/120359.asp Although I haven't seen nicks presentation with the phase diagram though. I learned about them from this project I did.

I once was writing a computer programming in C++ (I gues it probbly should have been in C) but I was eventually going to use stellar data for stars, and fmodel the contidions of littel icey moons orbiting the suspected extrasolar planets orbiting them. Using jsut black body radiation. up to that point I was fine. But to determind the state of something like water on them I needed to know at what state differet materials would be in at what temperture. . .

I've thoguh about how to incorporate phase diagrams int o any computer modeling program. It looks that they could be aproximated by a colleciton of graphed equations. (at least for water up to aroudn 10^8 Pa for waters) is this what is done? and where could I find somthing like that (doe sit cost money?)

I had spent hours looking for phase diagrams before and coudl never find much. I found them mainly for metals, I could only find two for popular compounds: CO2 or H20 and they were realy too rough to try to apporoximate or even use in any kind of modeling program (assuming black body radiators and not emisivity is rough enough, but If I couldn't find phase diagrams I knew I couldn't find any emisivity data. . . . )

you've done modeling like this before right? where can I get this type of data? By working on things like this I end up learning a lot, I had already learned atmospheric escape and black body radiation from what I had done. Heck I could post what I have of the source, although it won't compile as I stopped in the middle of a rewrite. . .

-Justin Kelly