Table 3. Number of Macroiterations to Converge the Molecular Geometry Optimization of the Dimers of the S22 Test Suite Using Conventional Restricted-Step Rational-Function (RS-RFO) and RVO Supported by GEK^a.

complex	RS-RFO	RVO	rmsd
Hydrogen-bonded Complexes
1: (NH3)2	5	6	0.000
2: (H2O)2	6	6	0.001
3: formic acid dimer	7	6	0.000
4: formamide dimer	7	6	0.000
5: uracil dimer HB	7	6	0.000
6: 2-pyridoxine·2-aminopyridine	15	16	0.001
7: adenine·thymine WC	18	14	0.001
Dispersion Dominated Complexes
8: (CH4)2	20	16	0.004
9: (C2H4)2	5	3	0.000
10: benzene·CH4	4	3	0.010
11: PD benzene dimer	7	15	0.000
12: pyrazine dimer	8	11	0.002
13: stacked uracil dimer	24	20	0.001
14: stacked indole·benzene	61	122	0.044
15: stacked adenine·thymine	29	23	0.002
Mixed Complexes
16: ethene·ethyne	6	6	0.000
17: benzene·H2O	35	29	0.002
18: benzene·NH3	33	29	0.002
19: benzene·HCN	31	7	0.027
20: T-shaped benzene dimer	5	7	0.000
21: T-shaped indole benzene	4	7	0.001
22: phenol dimer	21	17	0.003

^aHighlighted in bold are cases where the difference between the two methods is larger than 1 iteration.