III.G.1.a.

Comparison of levels of theory for F-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	1.6746 6
	PM3	1.6752 12
	PM6	1.6650 12
composite	G2	1.7380 11
	G3	1.7248 12
	G3B3	1.7345 12
	CBS-Q	1.7275 12

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	cc-pV(D+d)Z	cc-pV(T+d)Z	cc-pCVDZ	cc-pCVTZ
hartree fock	HF	1.8502 17	1.8547 17	1.7268 12	1.8589 15	1.7247 12	1.7248 12	1.7361 12	1.7472 12	1.7472 12	1.7008 12	1.5940 5	1.7217 12	1.7258 12	1.7009 12	1.5786 7	1.7400 12	1.7109 12	1.5785 7	1.6171 1	1.6927 12	1.6468 4	1.5969 9
hartree fock	ROHF					1.5311 1
density functional	LSDA	1.8563 11	1.7281 11	1.6741 11	1.8648 12	1.7112 12	1.7112 12	1.6793 11	1.6899 11	1.7360 12	1.6420 11			1.6847 11	1.6554 11		1.6887 11	1.5459 1		1.6361 1	1.6198 1
	SVWN		1.8395 12			1.7243 11		1.7236 12
	BLYP	1.9168 11	1.9147 17	1.7954 12	1.9948 4	1.7803 12	1.7803 12	1.7975 12	1.8389 7	1.8117 12	1.7580 12			1.8022 12	1.7723 12		1.7627 5			1.6656 1	1.6503 1
	B1B95	1.8489 11	1.7646 12	1.7198 12	1.8556 12	1.7094 12	1.7112 12	1.6686 11	1.7311 12	1.7311 12	1.6900 12			1.7292 12	1.6415 11	1.5306 1	1.6756 11	1.7229 7	1.5311 1	1.6371 1	1.6182 1
	B3LYP	1.8654 11	1.8480 12	1.7444 12	1.8774 12	1.7344 12	1.7344 12	1.7449 12	1.7571 12	1.7866 7	1.6594 11	1.6697 5	1.7538 12	1.7529 12	1.7218 12	1.6550 7	1.7543 11	1.7271 11	1.6552 7	1.6494 1	1.7098 12	1.7096 4	1.6708 9
	B3LYPultrafine					1.7341 12		1.7184 3
	B3PW91	1.8553 6	1.8370 12	1.7323 12	1.8666 12	1.7218 12	1.7219 12	1.6801 11	1.7422 12	1.7718 7	1.7003 12			1.7396 12	1.7071 12		1.6995 5			1.6423 1	1.6241 1
	mPW1PW91	1.8439 6	1.8238 12	1.7499 7	1.8547 12	1.7122 12	1.7122 12	1.6704 11	1.7310 12	1.7311 12	1.6907 12			1.7294 12	1.6456 11		1.6898 5			1.6383 1	1.6197 1
	M06-2X					1.6939 12														1.6347 1	1.6171 1
	PBEPBE	1.9011 6	1.8911 11	1.7962 7	1.9322 10	1.7543 12	1.7543 12	1.7181 11	1.7822 12	1.7823 12	1.7333 12	1.6906 5		1.7756 12	1.6914 11	1.5636 1		1.7030 4	1.5637 1	1.6548 1	1.6512 1
	PBEPBEultrafine					1.7092 5
	HSEh1PBE					1.7127 12														1.6390 1	1.6204 1
Moller Plesset perturbation	MP2FC		1.8659 12	1.7379 12	1.8732 11	1.6712 11	1.6712 11	1.7198 12	1.6921 11	1.6921 11	1.6351 6		1.7225 12	1.6951 11	1.6487 11	1.6296 1	1.7313 11	1.7393 3	1.6302 1	1.6815 1	1.6720 12	1.7027 4	1.6509 9
	MP2FU	7.0778 5	1.8635 11	1.7656 7	1.8604 6	1.6684 11	1.6685 11	1.7174 12	1.6907 11	1.6789 6	1.6304 6			1.6918 10	1.6358 6	1.6269 1	1.7101 9				1.6693 12	1.7021 4	1.6497 9
	MP3					1.6598 11															1.6208 1
	MP4		2.0538 2			1.7219 11			1.6886 1	1.7648 7					1.7236 6					1.6815 1	1.6412 1
	B2PLYP					1.7246 12		1.7389 12												1.6488 1	1.6292 1
Configuration interaction	CID		1.8529 7	1.7605 7	1.8483 7	1.6383 11			1.6361 7												1.6117 1
Configuration interaction	CISD		1.8452 7	1.7523 7	1.7858 6	1.6397 11			1.6349 6											1.6435 1	1.6133 1
Quadratic configuration interaction	QCISD		1.9053 7	1.7737 7	2.0511 2	1.6692 10	1.6592 6	1.7352 8	1.7402 11	1.7628 7	1.5531 1			1.7537 8	1.5900 2					1.6521 1	1.6279 1
Quadratic configuration interaction	QCISD(T)					1.8241 3			1.6891 1					1.9169 2	1.8652 2		1.8944 2	1.8589 2		1.6836 1	1.6386 1
Coupled Cluster	CCD		1.8886 7	1.7713 7	1.8844 7	1.6593 11	1.6496 6	1.7195 7	1.6636 7	1.5585 1	1.5306 1			1.6699 7	1.5264 1		1.8305 2	1.5294 1		1.6489 1	1.6209 1	1.6932 4	1.6407 4
	CCSD					1.6588 6			1.6753 1											1.6515 1	1.6233 1
	CCSD(T)		1.7868 1			1.6892 5	1.6734 1	1.6785 1	1.6886 1	1.6886 1		1.6422 1		1.8433 3	1.7933 3		1.8274 3	1.7899 3		1.6834 1	1.6465 6	1.7159 4	1.6591 4
	CCSD(T)=FULL					1.8227 3								1.6944 1	1.6422 1		1.6835 1	1.6422 1		1.6824 1	1.6436 6	1.7147 4	1.6575 4

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	1.8936 10	1.7374 11	1.8904 10	1.7390 11	1.8611 10	1.8607 10
density functional	B1B95	1.8453 5	1.6881 5
density functional	B3LYP	1.9122 11	1.7607 11	1.9083 11	1.7605 11	1.9146 11	1.9141 11
Moller Plesset perturbation	MP2FC	1.8400 4	1.6985 7	1.9107 5	1.7057 10	1.8509 4	1.9254 5

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.