III.G.1.a.

Comparison of levels of theory for N-C

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	1.3257 65
	PM3	1.3780 238
	PM6	1.3903 276
composite	G2	1.3700 211
	G3	1.3579 249
	G3B3	1.3633 253
	CBS-Q	1.3179 155
molecular mechanics	DREIDING	1.4603 6

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(T+d)Z	cc-pCVDZ	cc-pCVTZ	Sadlej_pVTZ
hartree fock	HF	1.3758 249	1.3328 274	1.3321 254	1.3296 254	1.3345 280	1.3219 254	1.3367 263	1.3212 253	1.3351 251	1.3317 253	1.3349 210	1.3096 5	1.3672 286	1.3248 252	1.3173 245	1.2745 60	1.3236 243	1.3188 239	1.2657 42	1.2198 5	1.2242 2	1.2162 2	1.4140 8
hartree fock	ROHF	1.2793 12	1.2399 14	1.2011 12	1.2068 12	1.2289 15	1.1944 12	1.1884 12	1.1834 12	1.2294 13	1.2312 13				1.2001 11	1.1857 11	1.2583 8	1.2427 12	1.2346 12	1.2301 7
density functional	LSDA	1.3970 259	1.3527 262	1.3534 263	1.3514 261	1.3434 261	1.3431 261	1.3421 260	1.3378 259	1.3395 259	1.3403 257			1.3389 8	1.3438 258	1.3362 258	1.2913 10	1.3433 251	1.2495 15	1.2824 8
	SVWN		1.3896 252			1.3857 242	1.3422 8	1.3823 249	1.3395 8	1.3397 8	1.3396 8				1.3432 8	1.3380 8
	BLYP	1.4282 249	1.3773 254	1.3621 168	1.3625 253	1.3540 248	1.3537 254	1.3540 251	1.3476 167	1.3652 249	1.3633 248			1.3584 8	1.3561 248	1.3478 252		1.3841 177
	B1B95	1.4035 266	1.3617 270	1.3620 270	1.3594 270	1.3498 252	1.3507 270	1.3505 266	1.3472 269	1.3483 269	1.3515 260	1.2871 1		1.3388 8	1.3514 268	1.3441 267	1.2577 15	1.3565 248	1.3195 49	1.2439 13
	B3LYP	1.4079 253	1.3508 271	1.3500 253	1.3481 254	1.3550 272	1.3516 254	1.3404 270	1.3357 248	1.3201 86	1.3371 241	1.3615 170	1.3214 5	1.3806 285	1.3574 253	1.3336 246	1.2854 43	1.3302 113	1.3255 102	1.2690 39	1.2448 5			1.4252 8
	B3LYPultrafine		1.3296 3			1.3581 247		1.3299 59					1.3228 3						1.3231 3
	B3PW91	1.3663 83	1.3469 254	1.3471 253	1.3444 253	1.3366 249	1.3359 253	1.3328 168	1.3349 250	1.3169 86	1.3464 248			1.3425 8	1.3373 252	1.3301 250		1.3665 176
	mPW1PW91	1.3686 96	1.3436 253	1.3373 103	1.3542 254	1.3333 247	1.3367 252	1.3326 252	1.3294 252	1.3449 251	1.3437 248			1.3401 8	1.3367 247	1.3214 127		1.3610 180	1.1892 3
	M06-2X	1.3682 9	1.3420 9	1.3420 9	1.3401 9	1.3819 264	1.3283 9	1.3290 9	1.3265 9	1.3266 9	1.3261 9			1.3411 8	1.3293 9	1.3252 9		1.2110 1	1.2016 1
	PBEPBE	1.3813 84	1.3697 252	1.3379 88	1.3380 87	1.3597 246	1.3591 246	1.3590 249	1.3565 248	1.3585 251	1.3689 244	1.3725 165	1.3282 5	1.3528 8	1.3578 234	1.3541 245	1.2790 14	1.3139 14	1.3231 48	1.2601 13	1.1682 1			1.4277 8
	PBEPBEultrafine		1.3371 3			1.3752 183		1.3397 6					1.3291 3						1.3294 3
	HSEh1PBE	1.3725 9	1.3398 9	1.3398 9	1.3404 9	1.3740 248	1.3281 9	1.3287 9	1.3260 9	1.3261 9	1.3262 9			1.3403 8	1.3292 9	1.3244 9		1.2133 1	1.2033 1
Moller Plesset perturbation	MP2FC	1.3740 86	1.3655 275	1.3637 250	1.3632 252	1.3576 277	1.3436 254	1.3470 273	1.3414 240	1.3442 248	1.3269 173		1.3234 2	1.3842 286	1.3620 252	1.3291 155	1.2180 9	1.3359 110	1.2631 29	1.2121 10	1.3028 3	1.2152 3	1.1999 3	1.4311 8
	MP2FU	1.3665 82	1.3562 129	1.3551 105	1.3519 105	1.3692 253	1.3357 163	1.3390 168	1.3396 251	1.3210 83	1.3081 84			1.3471 8	1.3418 129	1.3221 91	1.1805 8	1.3104 43	1.2553 13	1.2231 8	1.2442 5	1.2144 3	1.1979 3
	ROMP2	1.2687 9	1.2217 8	1.2217 8	1.2348 9	1.2183 8	1.2167 9	1.2098 9	1.2033 9	1.2033 9	1.2103 9				1.2239 8	1.2029 8	1.1927 3	1.2175 8	1.1949 4	1.1923 3
	MP3					1.3399 246
	MP4	1.3376 6	1.3490 66	1.3825 4	1.3388 3	1.3346 77			1.2669 4	1.3252 48	1.2519 4					1.2002 18
	B2PLYP	1.3807 9	1.3490 9	1.3490 9	1.3512 9	1.3898 253	1.3350 9	1.3895 256	1.3333 9	1.3334 9	1.3299 9			1.3470 8	1.3373 9	1.3282 9		1.2228 1	1.1848 1
Configuration interaction	CID	1.3923 2	1.3316 94	1.3368 92	1.3340 93	1.3293 165	1.3529 5	1.3535 5	1.3170 91	1.2615 8	1.2308 4				1.3565 5
Configuration interaction	CISD	1.4384 4	1.3389 99	1.3387 92	1.3361 93	1.3275 159	1.3990 9	1.3541 5	1.3185 88	1.2623 8	1.2315 4				1.3570 5
Quadratic configuration interaction	QCISD	1.2957 16	1.3729 187	1.3532 88	1.3418 95	1.3380 140	1.3207 93	1.3209 96	1.3274 117	1.3060 112	1.2736 42			1.3470 8	1.3323 99	1.2529 35		1.2033 3	1.1991 3		1.1584 1
Quadratic configuration interaction	QCISD(T)					1.3067 63		1.3099 2	1.3444 6	1.2912 5					1.2773 17	1.2732 15		1.2532 10	1.2496 8
Coupled Cluster	CCD	1.2933 16	1.3289 92	1.3414 89	1.3369 93	1.3493 176	1.3065 86	1.3081 84	1.3099 93	1.2682 43	1.2618 39			1.3440 8	1.3187 92	1.2668 32		1.2137 16	1.2200 11
	CCSD					1.3208 62		1.3315 2	1.2025 3	1.3028 1					1.2127 3	1.1978 3
	CCSD(T)		1.1845 3			1.3127 70	1.3339 10	1.2221 6	1.2744 4	1.2459 8		1.1731 1			1.2961 31	1.2589 33	1.1911 6	1.2627 27	1.2452 22	1.2017 4	1.1658 1	1.2255 3	1.2112 3
	CCSD(T)=FULL					1.2502 16									1.2134 8	1.2439 12	1.1988 5	1.2032 6	1.2628 7	1.1984 4		1.2247 3	1.1974 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	1.3457 254	1.3361 250	1.3421 254	1.3301 250	1.3375 254	1.3375 254
hartree fock	ROHF	1.1703 1		1.1645 1		1.1621 1	1.1615 1
density functional	B1B95	1.3835 208	1.3750 203	1.4393 5	1.4315 5	1.4363 5	1.4363 5
density functional	B3LYP	1.3663 252	1.3553 248	1.3619 253	1.3491 249	1.3561 253	1.3568 249
Moller Plesset perturbation	MP2FC	1.3873 253	1.3611 249	1.3798 254	1.3555 249	1.3771 254	1.3776 253
Moller Plesset perturbation	ROMP2	1.2362 1		1.2246 1		1.2224 1	1.2224 1

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.