Re: [ccp4bb] Freezing crystal

[Jim Pflugrath]

Just a thought for those that mentioned propane and ethane, I would like to 
suggest that they try carbon tetrafluoride (CF4) instead.  It certainly should 
be much safer.  It melts at 90 K and boils at 145 K, so you know you are below 
145 K if you see it as a liquid.