III.G.1.a.

Comparison of levels of theory for C-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	1.6996 27
	PM3	1.7282 110
	PM6	1.7389 133
composite	G2	1.7585 90
	G3	1.7583 123
	G3B3	1.7800 111
	CBS-Q	1.7575 103

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	Sadlej_pVTZ
hartree fock	HF	1.8041 129	1.8478 129	1.7727 129	1.8310 129	1.7588 133	1.7586 129	1.7614 129	1.7607 129	1.7605 123	1.7561 123	1.7526 95	1.7561 152	1.7646 129	1.7550 125	1.7285 31	1.7650 126	1.7551 120	1.7257 23	1.7836 1	1.7295 51	1.7823 1		1.7713 11
hartree fock	ROHF	1.7664 10	1.8348 21	1.7568 21	1.8209 17	1.7342 21	1.7342 21	1.7305 21	1.7347 21	1.7407 17	1.6895 10			1.7404 21	1.7284 21	1.7295 17	1.7430 17	1.7321 17	1.7282 17
density functional	LSDA	1.8216 123	1.8258 123	1.7663 123	1.8241 123	1.7539 123	1.7551 120	1.7514 123	1.7520 123	1.7521 123	1.7464 121			1.7549 123	1.7429 123	1.6909 9	1.7541 117	1.7333 18	1.6881 9	1.7627 1		1.7709 1	1.7616 1
	SVWN		1.8127 115			1.7547 112		1.7430 115
	BLYP	1.8661 129	1.8956 130	1.8165 110	1.8819 130	1.8067 130	1.8069 130	1.8047 130	1.8014 110	1.8071 124	1.7977 124			1.8077 130	1.7981 130		1.8174 86			1.8164 1		1.8247 1	1.8177 1
	B1B95	1.8245 123	1.8307 123	1.7747 123	1.8319 123	1.7618 116	1.7604 123	1.7582 123	1.7597 123	1.7598 123	1.7534 123			1.7622 123	1.7514 123	1.6747 11	1.7618 117	1.7612 19	1.6732 11	1.7718 1		1.7794 1	1.7731 1
	B3LYP	1.8410 129	1.8675 129	1.7950 129	1.8539 129	1.7814 129	1.7815 129	1.7796 129	1.7816 129	1.7629 38	1.7740 126	1.7738 88	1.7732 152	1.7838 129	1.7734 127	1.7448 23	1.7674 76	1.7515 63	1.7430 23	1.7954 1	1.7433 51	1.8036 1	1.7962 1	1.7936 11
	B3LYPultrafine					1.7807 120		1.7552 31
	B3PW91	1.8294 45	1.8523 127	1.7812 127	1.8384 127	1.7679 127	1.7680 127	1.7599 106	1.7664 127	1.7466 36	1.7599 121			1.7694 127	1.7598 127		1.7787 86			1.7806 1		1.7887 1	1.7807 1
	mPW1PW91	1.8223 48	1.8458 129	1.7618 52	1.8321 129	1.7622 129	1.7623 129	1.7597 128	1.7611 129	1.7607 123	1.7549 123			1.7642 129	1.7407 77		1.7752 97	1.7861 8		1.7755 1		1.7842 1	1.7759 1
	M06-2X	1.8389 3	1.8418 3	1.7848 3	1.8274 3	1.7445 118	1.7721 3	1.7708 3	1.7725 3	1.7725 3	1.7699 3			1.7755 3	1.7670 3		1.7744 3			1.7790 1		1.7858 1	1.7794 1
	PBEPBE	1.8465 47	1.8690 123	1.7889 35	1.8414 35	1.7812 123	1.7813 123	1.7790 123	1.7805 123	1.7808 123	1.7722 120	1.7723 87		1.7829 119	1.7719 121	1.6962 11	1.8074 11	1.7610 46	1.6943 11	1.7912 1	1.7107 2	1.7978 1	1.7914 1	1.7946 11
	PBEPBEultrafine					1.7865 91
	HSEh1PBE	1.8488 3	1.8465 3	1.7848 3	1.8324 3	1.7520 114	1.7706 3	1.7694 3	1.7707 3	1.7707 3	1.7676 3			1.7737 3	1.7648 3		1.7724 3	1.7634 2		1.7745 1		1.7824 1	1.7751 1
Moller Plesset perturbation	MP2FC	1.8273 47	1.8767 129	1.7851 129	1.8594 129	1.7592 130	1.7535 126	1.7518 129	1.7540 128	1.7523 123	1.7334 66		1.7544 152	1.7645 129	1.7402 85	1.7685 5	1.7546 73	1.7198 19	1.7078 3	1.7765 1	1.7234 48	1.7833 1	1.7745 1	1.7846 11
	MP2FU	1.8285 41	1.8674 77	1.7743 49	1.8479 49	1.7528 129	1.7478 109	1.7455 109	1.7528 129	1.7335 38	1.7148 32			1.7511 77	1.7154 45	1.7628 5	1.7609 21	1.7320 10	1.7361 2	1.7741 1	1.7200 51	1.7811 1	1.7707 1
	ROMP2	1.8194 12	1.8389 15	1.7745 12	1.8486 12	1.7257 15	1.7257 15	1.7190 15	1.7231 15	1.7259 12	1.7220 12			1.7376 15	1.7178 15	1.6816 10	1.7402 12	1.6866 10	1.5735 4
	MP3					1.7607 116
	MP4	1.8517 6	1.8845 48			1.7516 68			1.7317 2	1.7497 28					1.7617 24					1.7866 1		1.7936 1	1.7850 1
	B2PLYP	1.8598 3	1.8700 3	1.7968 3	1.8532 3	1.7599 114	1.7781 3	1.7571 118	1.7900 3	1.7900 3	1.7449 3			1.7860 3	1.7713 3		1.8206 3			1.7885 1		1.7948 1	1.7588 1
Configuration interaction	CID		1.8574 45	1.7704 42	1.8408 42	1.7479 110			1.7399 50
Configuration interaction	CISD	1.8400 6	1.8621 42	1.7721 42	1.8444 42	1.7490 107			1.7415 45
Quadratic configuration interaction	QCISD	1.8512 6	1.8788 118	1.7827 48	1.8600 49	1.7535 83	1.7488 49	1.7478 55	1.7520 74	1.7483 80	1.7219 27			1.7639 46	1.7341 30		1.8009 13	1.7855 10		1.7854 1	1.7101 2	1.7926 1	1.7826 1
Quadratic configuration interaction	QCISD(T)					1.7502 41			1.7663 6					1.7723 26	1.7336 23		1.7338 12	1.6566 4				1.7958 1	1.7860 1
Coupled Cluster	CCD	1.8497 6	1.8657 49	1.7748 43	1.8469 43	1.7547 116	1.7437 49	1.7448 50	1.7447 55	1.7355 30	1.7261 24			1.7583 46	1.7425 24		1.7610 26	1.7459 15		1.7815 1		1.7891 1	1.7798 1
	CCSD					1.7403 64			1.7293 2					1.7765 10	1.7637 10
	CCSD(T)		1.8327 2			1.7572 69	1.7446 7	1.7195 2	1.7340 2	1.7185 2		1.6531 1		1.7703 24	1.7225 30	1.8183 4	1.7698 24	1.7493 12		1.7884 1	1.7128 2	1.7955 1	1.7858 1
	CCSD(T)=FULL					1.7829 20								1.7968 12	1.7781 9	1.8782 2	1.8091 11	1.8114 4		1.7864 1		1.7933 1	1.7097 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	1.8320 129	1.7683 122	1.8308 129	1.7681 122	1.8271 129	1.8332 129
density functional	B1B95	1.8414 95	1.7784 92
density functional	B3LYP	1.8643 129	1.7965 122	1.8614 129	1.7951 122	1.8503 129	1.8534 129
Moller Plesset perturbation	MP2FC	1.8642 129	1.7719 122	1.8626 129	1.7704 122	1.8572 129	1.8667 129

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.