Assertion: americium | /r/AtLocation | its most stable α form
Facets:
value: with cell parameters
type: OTHER
value: at ambient conditions
type: TEMPORAL
Source sentences:
text: At ambient conditions, americium is present in its most stable α form which has a hexagonal crystal symmetry, and a space group P6 3 /mmc with cell parameters a = 346.8 pm and c = 1124 pm, and four atoms per unit cell.