Table 1.

Lowest energy configurations at different stoichiometric ratios

(h, k) = T	N	1:1	2:1	3:1	5:1
(1, 0) = 1	12	S	S	S	S
(1, 1) = 3	32	S		I
(2, 0) = 4	42	S	S		S
(2, 1) = 7	72	S	S	S	S
(3, 0) = 9	92	S		S
(2, 2) = 12	122	S
(3, 1) = 13	132	S	S	I	I
(4, 0) = 16	162	S	S		S
(3, 2) = 19	192	S	S	S	I
(4, 1) = 21	212	S		I
(5, 0) = 25	252	S	S	S	S
(3, 3) = 27	272	S		S
(4, 2) = 28	282	S	S		S
(5, 1) = 31	312	S	S	I	I
(6, 0) = 36	362	S
(4, 3) = 37	372	S	S	I	S
(5, 2) = 39	392	S		S
(6, 1) = 43	432	S	S	I	I
(4, 4) = 48	482	S

From left to right: T number, total number of charges, stoichiometric ratios. An empty entry means the configuration is not allowed because of global electroneutrality. We note that stoichiometric ratios 1:1 and 4:1 form square lattices on a plane, whereas the others form triangular lattices. However, the case 4:1 never fulfills the electroneutrality condition for any given T triangulation. The letters ″S″ and ″I″ indicate that the most stable structure is the sphere (S) or icosahedron (I), respectively.