III.G.1.a.

Comparison of levels of theory for Na-Li

Click on an entry for a histogram of the values.
The subscript refers to how many bonds of that type have been calculated.

average calculated bond lengths (Å)

Methods with predefined basis sets
semi-empirical	PM3	3.6170 1
semi-empirical	PM6	2.7199 3
composite	G2	3.3514 3
	G3	3.3514 3
	G3B3	3.1855 3
	CBS-Q	3.3514 3

average calculated bond lengths (Å)

Methods with standard basis sets
		STO-3G	3-21G	3-21G*	6-31G	6-31G*	6-31G**	6-31+G**	6-311G*	6-311G**	6-31G(2df,p)	6-311+G(3df,2p)	TZVP	cc-pVDZ	cc-pVTZ	cc-pVQZ	aug-cc-pVDZ	aug-cc-pVTZ	aug-cc-pVQZ	Sadlej_pVTZ
hartree fock	HF	2.6323 3	3.3589 3	3.3500 3	3.3516 3	3.3517 3	3.3514 3	3.3396 3	3.3453 3	3.3453 3	3.3569 3	3.0014 1	3.3296 3	3.3622 3	3.3484 3	3.3481 3	3.3571 3	3.3475 3	3.3474 3	2.9657 1
density functional	LSDA	2.5502 3	3.1649 3	3.1673 3	3.1440 3	3.1347 3	3.1347 3	3.1216 3	3.1197 3	3.1197 3	3.1158 3			3.1290 3	3.1138 3	3.2345 2	3.1145 3	3.2365 2	3.2279 2
	SVWN		3.1763 3			3.1348 3		3.1216 3
	BLYP	2.5900 3	3.2008 3	3.1883 3	3.2032 3	3.1906 3	3.1906 3	3.1634 3	3.1815 3	3.1815 3	3.1951 3			3.1752 3	3.1696 3
	B1B95	2.5902 3	3.2233 3	3.2238 3	3.1127 2	3.2053 3	3.2053 3	3.0855 2	3.0990 2	3.0990 2	3.3127 1			3.2018 3	3.0930 2	3.2784 1	3.2717 1	3.2667 1	3.2525 1
	B3LYP	2.5833 3	3.1987 3	3.1881 3	3.1947 3	3.1855 3	3.1855 3	3.1664 3	3.1752 3	3.1752 3	3.1853 3		3.2194 3	3.1748 3	3.1655 3	3.1597 3	3.1596 3	3.1115 2	3.1508 3	2.8596 1
	B3LYPultrafine					3.1854 3
	B3PW91	2.6044 3	3.2607 3	3.2514 3	3.2350 3	3.2288 3	3.2288 3	3.2178 3	3.2210 3	3.2210 3	3.2213 3			3.2261 3	3.2151 3
	mPW1PW91	2.6016 3	3.2567 3	3.2473 3	3.2339 3	3.2278 3	3.2278 3	3.2184 3	3.2220 3	3.2220 3	3.2213 3			3.2265 3	3.2156 3			2.9278 1	2.9270 1
	M06-2X					3.1713 3
	PBEPBE	2.5965 3	3.2243 3	3.2132 3	3.2137 3	3.2039 3	3.2039 3	3.1909 3	3.1997 3	3.1997 3	3.2002 3			3.1982 3	3.1899 3	3.3189 2			3.3057 2	2.8943 1
	HSEh1PBE					3.2161 3
Moller Plesset perturbation	MP2FC	2.6221 3	3.3238 3	3.3070 3	3.3110 3	3.2958 3	3.2958 3	3.2893 3	3.2866 3	3.2866 3	3.2946 3		3.3003 3	3.3128 3	3.2852 3	3.2860 3	3.3090 3	3.2879 3	2.9730 1	2.9451 1
	MP2FU	2.5964 3	3.3205 3	3.2981 3	3.3059 3	3.2784 3	3.2784 3	3.2718 3	3.2578 3	3.2578 3	3.1697 3			3.2997 3	3.2267 3	3.0707 3	2.9671 1	2.9067 1	2.8516 1
	MP3					3.1882 2
	MP4		3.2907 3			3.2590 3	2.9577 1	2.9605 1		3.4019 2				2.9745 1	2.9585 1
	B2PLYP					3.2096 3		3.1926 3
Configuration interaction	CID		3.2854 3	3.2689 3	3.2706 3	3.2575 3			3.2499 3
Configuration interaction	CISD		3.2136 2	3.2058 2	3.2094 2	3.1956 2			3.1864 2
Quadratic configuration interaction	QCISD	2.4631 1	3.2852 3	3.2669 3	3.2754 3	3.2572 3	3.2572 3	3.2521 3	3.2455 3	3.2455 3	3.2586 3			3.2710 3	3.2496 3
Quadratic configuration interaction	QCISD(T)					3.2548 3	2.9533 1	2.9563 1	2.9405 1	2.9405 1	2.9500 1			3.2678 3	3.2454 3		3.2660 3	3.2466 3
Coupled Cluster	CCD	2.4539 1	3.2854 3	3.2689 3	3.2707 3	3.2575 3	3.2575 3	3.2571 3	3.2499 3	3.2499 3	3.2604 3			3.2760 3	3.2555 3		3.4312 2	3.4131 2
	CCSD					3.2586 3	2.9533 1	2.9563 1	2.9405 1	2.9405 1	2.9499 1			2.9679 1	2.9505 1		2.9682 1	2.9509 1
	CCSD(T)		3.0005 1			3.1643 2	2.9533 1	2.9563 1	2.9405 1	2.9405 1	2.9500 1			3.2690 3	3.2464 3	2.9496 1	3.2672 3	3.2478 3	2.9492 1
	CCSD(T)=FULL					3.1832 2								2.9549 1	2.8956 1		2.9410 1	2.8779 1

average calculated bond lengths (Å)

Methods with effective core potentials (select basis sets)
		CEP-31G	CEP-31G*	CEP-121G	CEP-121G*	LANL2DZ	SDD
hartree fock	HF	3.4014 2	3.4118 3	3.3729 3	3.3599 3	3.4070 3	3.3479 3
density functional	B1B95	3.0514 1	3.0328 1
density functional	B3LYP	3.3543 3	3.3235 3	3.2865 3	3.2680 3	3.3230 3	3.1872 3
Moller Plesset perturbation	MP2FC	3.4141 3	3.3549 3	3.3335 3	3.3033 3	3.3842 3	3.3107 3

For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.