III.G.1.a.

Comparison of levels of theory for N-Al

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	1.4913 3
	PM3	1.7166 3
	PM6	1.6380 4
composite	G2	1.7679 4
	G3	1.7679 4
	G3B3	1.7425 4
	CBS-Q	1.7685 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)	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	1.6716 4	1.8788 4	1.8391 4	1.9173 4	1.7679 4	1.7679 4	1.7746 4	1.8287 4	1.8287 4	1.8041 4	1.8243 1	1.7717 4	1.7979 4	1.7633 4	1.8057 4	1.8873 4	1.7656 4	1.8072 4	1.8350 1	1.8219 1	1.8574 1	1.8238 1
hartree fock	ROHF	1.7663 1	1.8581 1			1.7855 3	1.8275 1	1.8390 1		1.8234 1	1.8151 1			1.8529 1	1.8258 1					1.8293 1	1.8179 1	1.8511 1	1.8198 1
density functional	LSDA	1.7315 4	1.7465 4	1.7365 4	1.7804 4	1.7259 4	1.7259 4	1.7300 4	1.7230 4	1.7230 4	1.7127 4			1.7846 4	1.7195 4	1.6963 1	1.7451 4	1.7028 3	1.6975 1	1.7722 1	1.7630 1	1.7908 1	1.7655 1
	SVWN		1.7715 4			1.8502 2		1.7299 4
	BLYP	1.7617 4	1.8492 4	1.8098 4	1.8700 4	1.8030 4	1.8030 4	1.8083 4	1.8009 4	1.8009 4	1.7873 4			1.8190 4	1.7960 4					1.8044 1	1.7963 1	1.8231 1	1.7986 1
	B1B95	1.6832 4	1.7586 4	1.7479 4	1.7975 4	1.7378 4	1.7379 4	1.7428 4	1.7352 4	1.7352 4	1.7256 4			1.7556 4	1.7341 4	1.6871 2	1.7536 3	1.7147 3	1.6884 2	1.7966 1	1.7875 1	1.8174 1	1.7898 1
	B3LYP	1.6917 4	1.7869 4	1.7511 4	1.8017 4	1.7425 4	1.7425 4	1.7484 4	1.7406 4	1.7406 4	1.7294 4		1.7457 4	1.7588 4	1.7382 4	1.7252 3	1.7652 4	1.7397 4	1.7332 4	1.7981 1	1.7895 1	1.8182 1	1.7917 1
	B3LYPultrafine					1.7227 3
	B3PW91	1.6862 4	1.7859 4	1.7498 4	1.7981 4	1.7390 4	1.7390 4	1.7434 4	1.7362 4	1.7362 4	1.7264 4			1.7561 4	1.7342 4					1.7967 1	1.7868 1	1.8172 1	1.7893 1
	mPW1PW91	1.6828 4	1.7843 4	1.7489 4	1.7967 4	1.7395 4	1.7395 4	1.7442 4	1.7369 4	1.7369 4	1.7244 4			1.7575 4	1.7355 4					1.7966 1	1.7864 1	1.8175 1	1.7890 1
	M06-2X					1.7378 4														1.8003 1	1.7955 1	1.8208 1	1.7985 1
	PBEPBE	1.7516 4	1.8442 4	1.8046 4	1.8610 4	1.7947 4	1.7947 4	1.7990 4	1.7915 4	1.7915 4	1.7802 4			1.8120 4	1.7877 4	1.7777 3	1.7038 1	1.7411 2	1.7785 3	1.7997 1	1.7900 1	1.8185 1	1.7920 1
	PBEPBEultrafine					1.8035 1
	HSEh1PBE					1.7575 2														1.7976 1	1.7872 1	1.8185 1	1.7893 1
Moller Plesset perturbation	MP2FC	1.6699 4	1.7621 4	1.7217 4	1.7750 4	1.7242 4	1.7242 4	1.7286 4	1.7055 4	1.7055 4	1.6988 4		1.7416 3	1.7423 4	1.7174 4	1.8144 1	1.7372 4	1.6842 3	1.8163 1	1.8303 1	1.8143 1	1.8500 1	1.8159 1
	MP2FU	1.6704 4	1.7626 4	1.7218 4	1.7754 4	1.7236 4	1.7236 4	1.7277 4	1.7049 4	1.7049 4	1.6933 4			1.7418 4	1.7126 4	1.7855 1	1.7639 2	1.6345 1		1.8282 1	1.8076 1	1.8500 1	1.8115 1
	ROMP2																			1.8299 1	1.8177 1	1.8500 1	1.8196 1
	MP3					1.7371 4														1.8320 1	1.8149 1	1.8528 1	1.8164 1
	MP4	1.7618 1	1.7715 4			1.7353 4				1.7205 4	1.8178 1				1.7541 3					1.8351 1	1.8169 1	1.8553 1	1.8177 1
	B2PLYP					1.7338 4		1.7405 4												1.8028 1	1.7911 1	1.8233 1	1.8043 1
Configuration interaction	CID	1.7574 1	1.7800 4	1.7456 4	1.7957 4	1.7400 4		1.8374 1	1.7331 4	1.8199 1	1.8143 1			1.8541 1	1.8214 1
Configuration interaction	CISD	1.7535 1	1.8182 3	1.7787 3	1.8333 3	1.7453 4		1.8247 1	1.7412 4	1.8166 1	1.8109 1			1.8510 1	1.8181 1
Quadratic configuration interaction	QCISD	1.7541 1	1.8124 4	1.7755 4	1.8274 4	1.7597 4	1.7597 4	1.7644 4	1.7564 4	1.7564 4	1.7464 4			1.7811 4	1.7476 4					1.8235 1	1.8031 1	1.8437 1	1.8044 1
Quadratic configuration interaction	QCISD(T)	1.7563 1				1.7676 4				1.8122 1	1.8061 1			1.7897 4	1.7555 4		1.7794 3	1.7390 3		1.8265 1	1.8046 1	1.8461 1	1.8061 1
Coupled Cluster	CCD	1.7575 1	1.7789 4	1.7422 4	1.7942 4	1.7404 4	1.7404 4	1.7450 4	1.7300 4	1.7300 4	1.7215 4			1.7620 4	1.7318 4		1.7361 3	1.6805 2		1.8323 1	1.8153 1	1.8530 1	1.8169 1
	CCSD					1.7594 3				1.8098 1	1.8038 1			1.8447 1	1.8106 1					1.8223 1	1.8033 1	1.8427 1	1.8048 1
	CCSD(T)	1.7541 1				1.7579 2				1.8106 1	1.8046 1			1.7763 4	1.7447 4	1.6764 1	1.8107 3	1.7478 4		1.8246 1	1.8033 1	1.8442 1	1.8047 1
	CCSD(T)=FULL					1.7735 3								1.8455 1	1.8060 1	1.6577 1	1.8578 1	1.8050 1		1.8243 1	1.7975 1	1.8451 1	1.8012 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	1.9123 4	1.7710 4	1.9060 4	1.7762 4	1.8831 4	1.8317 4
density functional	B1B95	1.8743 1	1.8114 1
density functional	B3LYP	1.7978 4	1.7482 4	1.8020 4	1.7521 4	1.7887 4	1.7826 4
Moller Plesset perturbation	MP2FC	1.7728 4	1.7265 4	1.7706 4	1.7271 4	1.7713 4	1.7655 4

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.