Table 1.

Relative energies of Ph₂Te₂ conformers (kcal mol⁻¹), Te–Te bond lengths (R, Å) and amplitudes of the Ψ and Φ_1,2 dihedral angles (°) calculated with 23 different functionals combined with the TZ2P basis set; scalar ZORA effects were included in the calculations. Open conformer is taken as reference in the ΔE calculation.

Functional	R	Ψ	Φ1,2	R	Ψ	Φ1,2	ΔE
LDA	2.69	−79	81	2.65	−82	17	−2.1
BLYP	2.78	−87	97	2.74	−93	17	0.7
BP86	2.74	−86	98	2.70	−90	11	-a
OLYP	2.73	−87	98	2.70	−91	15	1.0
PBE	2.73	−85	93	2.70	−89	15	−0.4
OPBE	2.69	−87	100	2.66	−89	10	0.5
RPBE	2.75	−86	95	2.71	−90	15	0.5
revPBE	2.74	−86	97	2.71	−90	14	0.4
HTBS	2.71	−86	97	2.67	−89	10	0.1
PW91	2.73	−86	89	2.69	−88	13	−0.3
mPBE	2.74	−85	94	2.70	−89	15	−0.1
mPW	2.74	−86	98	2.70	−89	11	- a
TPSS	2.73	−85	95	2.69	−90	16	0.0
M06-L	2.76	−60	96	2.70	−83	19	−1.5
B3LYP	2.74	−90	93	2.71	−97	27	0.9
PBE0	2.70	−88	90	2.67	−93	21	0.1
OPBE0	2.67	−89	96	2.64	−92	15	0.6
mPW1PW	2.71	−90	91	2.68	−94	23	-a
M06	2.73	−79	94	2.70	−93	26	-a
TPSSH	2.71	−86	94	2.68	−91	19	−0.3
BLYP-D3(BJ)	2.77	−69	89	2.70	−90	25	0.1
BP86-D3(BJ)	2.74	−60	95	2.69	−82	17	−0.1
PBE-D3(BJ)	2.73	−77	87	2.69	−84	17	−0.6

^a The difference is smaller than 0.1 kcal mol⁻¹.