III.G.1.a.

Comparison of levels of theory for Br-Cl

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	AM1	2.1404 2
	PM3	2.3130 2
	PM6	2.4314 3
composite	G2	2.3328 3
composite	CBS-Q	2.4185 2

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
hartree fock	HF	2.4314 2	2.6417 3	2.3224 3	2.6355 3	2.3329 3	2.3328 3	2.3313 3	2.3402 3	2.3402 3	2.3026 3	2.1228 1	2.3356 3	2.3337 3	2.3128 3	2.1252 1	2.3354 3	2.3122 3	2.1251 1
hartree fock	ROHF					2.4288 2
density functional	LSDA	2.3633 3	2.3651 3	2.3040 3	2.4458 3	2.3226 3	2.3226 3	2.3182 3	2.3306 3	2.3306 3	2.2858 3			2.3261 3	2.3001 3		2.4391 2	2.6986 1
	SVWN		2.4632 3			2.3226 3		2.3182 3
	BLYP	2.5181 2	2.5589 3	2.4029 3	2.5417 3	2.4299 3	2.4299 3	2.4248 3	2.4413 3	2.4413 3	2.3920 3			2.4358 3	2.4135 3		2.2226 1
	B1B95	2.3700 3	2.3859 3	2.3251 3	2.4613 3	2.3423 3	2.3434 3	2.3406 3	2.3515 3	2.3515 3	2.3103 3			2.3476 3	2.3234 3		2.4784 2	2.4103 2
	B3LYP	2.3912 3	2.5117 3	2.3589 3	2.4934 3	2.3802 3	2.3802 3	2.3770 3	2.3892 3	2.3892 3	2.3455 3		2.3860 3	2.3840 3	2.3625 3	2.1660 1	2.3786 3	2.3582 3	2.1658 1
	B3LYPultrafine					2.4778 2
	B3PW91	2.4603 2	2.4893 3	2.3336 3	2.4695 3	2.3517 3	2.3517 3	2.3480 3	2.3582 3	2.3582 3	2.3175 3			2.3553 3	2.3309 3		2.1681 1
	mPW1PW91	2.3303 3	2.4776 3	2.3223 3	2.4577 3	2.3392 3	2.3392 3	2.3360 3	2.3458 3	2.3458 3	2.3059 3			2.3427 3	2.3190 3		2.1605 1
	M06-2X					2.3249 3
	PBEPBE	2.4896 2	2.5175 3	2.3577 3	2.5000 3	2.3797 3	2.3797 3	2.3754 3	2.3887 3	2.3887 3	2.3425 3	2.1584 1		2.3838 3	2.3586 3		2.1869 1	2.1662 1
	PBEPBEultrafine					2.1807 1
	HSEh1PBE					2.3412 3
Moller Plesset perturbation	MP2FC	2.4172 2	2.4771 3	2.3017 3	2.4604 3	2.3168 3	2.3168 3	2.3172 3	2.3214 3	2.3214 3	2.2829 3		2.3163 3	2.3226 3	2.2833 3	2.1244 1	2.3278 3	2.2812 3
	MP2FU	2.4171 2	2.4771 3	2.3008 3	2.4602 3	2.3140 3	2.3140 3	2.3142 3	2.3187 3	2.3187 3	2.2737 3			2.3216 3	2.2783 3	2.1211 1	2.1799 1
	MP3					2.3280 3
	MP4		2.4909 3			2.3345 3				2.4186 2					2.1559 1
	B2PLYP					2.3560 3		2.3550 3
Configuration interaction	CID		2.4910 3	2.3113 3	2.4727 3	2.3260 3			2.3302 3	2.1672 1
Configuration interaction	CISD		2.6149 2	2.3155 3	2.6073 2	2.3308 3			2.3350 3	2.1691 1
Quadratic configuration interaction	QCISD		2.5332 3	2.3320 3	2.5191 3	2.3485 3	2.3485 3	2.3497 3	2.3547 3	2.3547 3	2.3079 3			2.3526 3	2.3119 3
Quadratic configuration interaction	QCISD(T)					2.3529 3								2.4357 2	2.3949 2		2.4463 2	2.7170 1
Coupled Cluster	CCD		2.4932 3	2.3146 3	2.4764 3	2.3299 3	2.3299 3	2.3313 3	2.3351 3	2.3351 3	2.2968 3			2.3362 3	2.3768 2		2.4193 2	2.3732 2
	CCSD					2.3460 3
	CCSD(T)					2.1888 1						2.1546 1		2.3553 3	2.3149 3		2.3638 3	2.3143 3
	CCSD(T)=FULL					2.4304 2

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	2.5591 2		2.5572 2		2.7206 3	2.6325 3
density functional	B1B95	2.3030 1
density functional	B3LYP	2.4983 3		2.4982 3		2.5242 3	2.5051 3
Moller Plesset perturbation	MP2FC	2.4617 3		2.4607 3		2.4715 3	2.4624 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.