III.G.1.a.

Comparison of levels of theory for H-K

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	PM6	1.6451 1
composite	G2	2.3223 1

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
hartree fock	HF		2.3608 1	2.3527 1	2.3605 1	2.3223 1	2.3203 1	2.3204 1	2.3067 1	2.3069 1	2.3127 1	2.3077 1	2.3864 1
density functional	LSDA	2.0945 1	2.2973 1	2.2848 1	2.2938 1	2.2535 1	2.2505 1	2.2505 1	2.1999 1	2.1990 1	2.2306 1
	SVWN		2.2972 1			2.2531 1		2.2502 1
	BLYP		2.3423 1	2.3240 1	2.3358 1	2.2995 1	2.2965 1	2.2965 1	2.2525 1	2.2519 1	2.2754 1
	B1B95					2.2841 1
	B3LYP		2.3271 1	2.3134 1	2.3223 1	2.2852 1	2.2827 1	2.2827 1	2.2440 1	2.2438 1	2.2637 1		2.3368 1
	B3LYPultrafine					2.2848 1
	B3PW91		2.3333 1	2.3202 1	2.3256 1	2.2849 1	2.2824 1	2.2825 1	2.2411 1	2.2406 1	2.2637 1
	mPW1PW91		2.3267 1	2.3162 1		2.2803 1	2.2779 1	2.2779 1	2.2389 1	2.2384 1	2.2606 1
	M06-2X					2.2756 1
	PBEPBE		2.3386 1	2.3223 1	2.3319 1	2.2925 1	2.2895 1	2.2895 1	2.2433 1	2.2422 1	2.2696 1
	PBEPBEultrafine					2.2919 1
	HSEh1PBE					2.2800 1
Moller Plesset perturbation	MP2FC		2.3824 1	2.3671 1	2.3779 1	2.3178 1	2.2961 1	2.2964 1	2.2628 1	2.2432 1	2.2823 1		2.3765 1
	MP2FU		2.3817 1	2.3636 1	2.3779 1	2.3178 1	2.2961 1	2.2964 1	2.2619 1	2.2412 1	2.2822 1
	MP3					2.3262 1
	MP4		2.4033 1			2.3323 1
	B2PLYP					2.2928 1		2.2845 1
Configuration interaction	CID		2.4051 1	2.3867 1	2.3958 1	2.3343 1			2.2760 1
Configuration interaction	CISD		2.4190 1	2.3963 1	2.4093 1	2.3420 1			2.2770 1
Quadratic configuration interaction	QCISD		2.4190 1	2.3963 1	2.4095 1	2.3469 1	2.3161 1	2.3165 1	2.2920 1
Quadratic configuration interaction	QCISD(T)					2.3473 1
Coupled Cluster	CCD		2.4051 1	2.3867 1	2.3959 1	2.3362 1	2.3064 1	2.3068 1	2.2820 1
	CCSD					2.3475 1
	CCSD(T)					2.3475 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	2.3465 1		2.4595 1		2.3533 1	2.3460 1
density functional	B1B95	2.3578 1
density functional	B3LYP	2.3561 1		2.4448 1		2.3200 1	2.3091 1
Moller Plesset perturbation	MP2FC	2.3650 1		2.4590 1		2.3733 1	2.3553 1

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.