Assertion: crystalline compound | /r/HasProperty | important
Facets:
value: particularly
type: DEGREE
Source sentences:
text: Particularly important are crystalline compounds of C 60 with alkali metals and alkaline earth metals; these compounds are the only molecular systems to exhibit superconductivity at relatively high temperatures above 19 K. Superconductivity is observed in the range 19 to 40 K, equivalent to