Study of Hardness of Superhard Crystals by Topological Indices

Table 2

Hardness (H) of crystals , , , , , , , , , , , and .

Crystal	Symmetry	Hardness	Reference
		56	[28]
		65.8	[26]
		61.9	[26]
		64.8	[26]
		80	[30]
		74	[25]
		70	[25]
		77.6	[29]
		65.3	[27]
		80.7	[27]
		75.2	[27]
		65.4	[27]