A likely candidate among these substances is the pinacol  doped with CrV but there is certainly a lot of other possible candidates. CONCLUSION ... Chapellier : With methane, you would be faced with the transmission problem of heat.
|Title||:||Liquid and solid helium|
|Author||:||Charles Goethe Kuper, Stephen G. Lipson, M. Revzen, European Physical Society|
|Publisher||:||Halsted Press - 1975-01|