III.G.1.a.

Comparison of levels of theory for O-H

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	1.0080 40
	PM3	1.0143 130
	PM6	1.0642 170
composite	G2	1.0381 135
	G3	0.9755 118
	G3B3	1.0445 130
	CBS-Q	0.9760 99
molecular mechanics	DREIDING	0.9811 4

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)	6-311+G(3df,2pd)	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	1.0414 114	1.0358 161	0.9971 120	0.9840 119	1.0242 168	0.9703 122	1.0205 154	0.9654 122	0.9675 119	0.9679 119	1.0158 109	1.2076 35	1.0339 171	0.9733 121	0.9677 117	0.9499 51	1.0009 116	1.0182 142	0.9725 49	0.9499 1	0.9434 1	0.9538 2	0.9510 1	0.9454 5
hartree fock	ROHF	1.0149 5	0.9787 17	0.9788 17	0.9674 15	0.9633 21	0.9538 17	0.9551 17	0.9489 17	0.9557 11	0.9578 6			0.9410 2	0.9596 15	0.9534 15	0.9654 6	0.9585 11	0.9569 10	0.9655 6
density functional	LSDA	1.1002 147	1.0618 155	1.0786 156	1.0623 151	1.0370 151	1.0517 152	1.0501 152	1.0495 152	1.0487 152	1.0493 150			1.2059 7	1.0552 150	1.0465 152	0.9983 5	1.0450 144	0.9894 28	0.9989 5	0.9837 1		0.9839 1	0.9766 1
	SVWN		1.0988 147			1.0695 141	1.2023 7	1.0614 146	1.2037 7	1.2021 7	1.1908 7				1.2101 7	1.1946 7		1.2094 7	0.9756 3
	BLYP	1.1103 114	1.0487 121	1.0498 107	1.0277 120	1.0370 122	1.0092 122	1.0078 122	1.0101 106	1.0047 118	1.0055 119			1.2293 7	1.0303 117	1.0058 113		0.9790 64			0.9871 1		0.9874 1	0.9780 1
	B1B95	1.0778 136	1.0500 150	1.0446 144	1.0380 149	1.0278 138	1.0292 150	1.0539 148	1.0187 143	1.0197 141	1.0239 139			1.1881 7	1.0313 147	1.0211 143	0.9900 15	1.0132 129	0.9758 34	0.9861 15	0.9697 1		0.9698 1	0.9624 1
	B3LYP	1.0854 114	1.0911 158	1.0290 120	1.0117 121	1.0612 158	0.9965 121	1.0421 162	0.9925 122	1.0181 62	0.9932 118	0.9630 59	1.2047 33	1.0495 168	0.9996 120	0.9929 116	0.9926 51	1.0240 92	1.0708 115	0.9936 47	0.9751 1	0.9668 1	0.9752 1	0.9669 1	0.9684 5
	B3LYPultrafine		1.1799 35			1.0497 146		1.0940 62					1.1905 35						1.1909 35
	B3PW91	1.1002 61	1.0289 120	1.0254 121	1.0092 121	0.9981 119	0.9940 121	0.9964 108	0.9903 122	1.0158 62	0.9914 118			1.1949 7	0.9988 117	0.9911 116		0.9666 64			0.9730 1		0.9732 1	0.9653 1
	mPW1PW91	1.0976 68	1.0248 122	1.0417 75	1.0060 121	1.0189 119	0.9913 121	0.9902 121	0.9875 122	0.9876 119	0.9887 118			1.1894 7	0.9961 117	0.9956 93		0.9855 83	0.9718 15		0.9705 1		0.9707 1	0.9629 1
	M06-2X	1.0202 11	1.1413 12	1.1220 12	1.1305 12	1.0602 152	1.0883 13	1.0987 12	1.0861 13	1.0857 13	1.0825 13			1.1844 7	1.1027 12	1.0925 12		1.0907 13	0.9716 8		0.9711 1	0.9643 1	0.9712 1	0.9643 1
	PBEPBE	1.1263 61	1.1099 150	1.0699 68	1.0526 65	1.0570 148	1.0066 120	1.0483 151	1.0032 121	1.0021 119	1.0730 118	0.9722 61	1.3819 31	1.2178 7	1.0103 120	1.0163 120	1.0043 15	1.0622 35	1.0761 86	0.9998 15	0.9849 1	0.9763 1	0.9851 1	0.9765 1	0.9771 5
	PBEPBEultrafine		1.1822 35			1.0642 105		1.1676 39					1.1891 35						1.1897 35
	HSEh1PBE	1.1844 12	1.1366 13	1.1240 12	1.1382 12	1.0631 141	1.0995 12	1.1011 12	1.0881 13	1.0882 13	1.0837 13			1.1905 7	1.1054 12	1.0845 13		1.0932 13	0.9702 8		0.9712 1	0.9638 1	0.9714 1	0.9638 1
Moller Plesset perturbation	MP2FC	1.0814 60	1.0868 163	1.0239 120	1.0139 118	1.0545 163	0.9934 122	1.0350 165	0.9885 120	0.9887 119	1.0148 95	0.9594 4	1.1669 34	1.0472 170	0.9967 121	1.0198 101	0.9866 18	1.0051 91	1.0630 85	0.9856 16	0.9733 1	0.9665 1	0.9678 8	0.9632 6	0.9705 5
	MP2FU	1.0882 54	1.0340 96	1.0471 68	1.0383 67	1.0011 123	0.9966 107	0.9975 106	0.9888 118	1.0132 62	1.0162 60			1.1961 7	1.0053 92	1.0095 67	0.9893 15	1.0129 43	0.9765 22	0.9874 14	0.9727 1	0.9650 1	0.9672 8	0.9623 6
	ROMP2	1.0416 10	1.0144 10	1.0144 10	1.0005 10	0.9930 10	0.9843 10	0.9847 11	0.9785 10	0.9793 10	0.9803 9			0.9640 1	0.9864 11	0.9809 10	0.9879 3	0.9873 10	0.9834 6	0.9780 3
	MP3					0.9979 117																0.9588 1
	MP4	1.0265 3	1.0215 60	1.0003 7	0.9848 8	1.0731 77	0.9752 1	0.9770 1	0.9618 21	1.0273 35	0.9572 2				0.9780 1	1.0053 48					0.9735 1	0.9667 1	0.9737 1	0.9667 1
	B2PLYP	1.0243 11	1.1465 13	1.1210 13	1.1420 13	1.0740 152	1.1051 12	1.0591 154	1.0935 13	1.0936 13	1.0862 13			1.2012 7	1.1014 13	1.0866 13		1.1011 13	0.9593 7		0.9731 1	0.9658 1	0.9732 1	0.9658 1
Configuration interaction	CID	1.0136 2	1.0372 63	1.0352 60	1.0243 59	1.0182 105	0.9613 2	0.9619 2	0.9803 77	0.9537 7	0.9485 2				0.9636 2	0.9557 10
Configuration interaction	CISD	1.0140 2	1.0326 74	1.0365 61	1.0243 61	1.0162 104	0.9592 5	0.9626 2	0.9964 60	0.9541 7	0.9439 1				0.9644 2	0.9565 10
Quadratic configuration interaction	QCISD	1.0891 15	1.0556 107	1.0452 68	1.0090 63	1.0071 98	1.0093 72	1.0029 82	0.9955 89	1.0292 70	1.0200 45			1.1901 7	1.0395 102	1.0089 61		1.0704 17	0.9736 11		0.9713 1	0.9622 1	0.9714 1	0.9622 1
	QCISD(T)		0.9977 4	0.9967 2	0.9653 1	1.0731 71	0.9674 11	0.9688 15	0.9616 22	0.9627 7	0.9656 1			1.2397 6	1.0212 46	1.0185 39		1.0751 19	0.9916 14		0.9734 1	0.9622 1	0.9736 1	0.9653 1
	QCISD(TQ)					0.9713 2													0.9616 2
Coupled Cluster	CCD	1.0870 15	1.0421 76	1.0486 61	1.0334 66	1.0026 107	1.0075 72	1.0082 69	0.9959 83	1.0213 49	1.0171 46	0.9595 3		1.1832 7	1.0379 102	1.0013 50		1.0239 35	0.9797 27		0.9697 1	0.9608 1	0.9698 1	0.9608 1
	CCSD		0.9944 4	0.9940 2	0.9714 2	1.0892 66	0.9661 11	0.9676 14	1.0392 22	0.9583 4	0.9488 1				1.0303 28	1.0237 26
	CCSD(T)		1.1160 28	0.9865 1	0.9652 1	1.1584 96	0.9660 25	1.0653 30	0.9623 19	0.9632 11	0.9579 2	0.9644 6	1.0519 11	1.2374 6	1.0211 45	1.0252 48	0.9916 13	1.0270 37	1.0081 34	0.9866 11	0.9733 1	0.9651 1	0.9713 4	0.9637 4
	CCSD(T)=FULL					1.0453 34								1.2366 6	1.0591 20	0.9725 11	0.9899 11	1.0595 20	0.9699 8	0.9852 11	0.9728 1	0.9637 1	0.9708 4	0.9628 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	0.9895 120	0.9798 115	0.9833 121	0.9973 132	1.0037 138	0.9866 121
density functional	LSDA	1.0165 1	0.9999 1	1.0140 1	0.9967 1	1.0118 1	1.0118 1
	B1B95	1.0669 107	1.0800 111	1.1374 6	1.1196 6	1.1384 6	1.1383 6
	B3LYP	1.0187 119	1.0066 112	1.0124 121	1.0201 130	1.0078 134	0.9983 120
	B3LYPultrafine				0.9757 2	1.2908 3
Moller Plesset perturbation	MP2FC	1.0045 119	1.0080 115	0.9994 118	1.0223 131	1.0191 136	1.0017 119

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.