III.G.1.a.

Comparison of levels of theory for P-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	1.3192 15
	PM3	1.2916 29
	PM6	1.4561 29
composite	G2	1.4024 28
	G3	1.4024 28
	G3B3	1.4274 29
	CBS-Q	1.4024 28

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(T+d)Z	cc-pCVDZ	cc-pCVTZ
hartree fock	HF	1.3906 27	1.4230 29	1.4016 29	1.4276 29	1.4026 29	1.4048 29	1.4044 29	1.4057 29	1.4076 29	1.4062 28	1.4079 14	1.4125 29	1.4191 29	1.4091 29	1.4061 29	1.4184 29	1.4083 29	1.4057 29	1.4038 17	1.4176 3	1.4056 3
hartree fock	ROHF	1.4001 8	1.4249 11	1.4022 11	1.4269 8	1.4063 12	1.4056 11	1.4051 11	1.4061 11	1.4067 8	1.4057 8			1.4202 11	1.4101 11	1.4059 8	1.4180 8	1.4077 8	1.4051 8
density functional	LSDA	1.4279 29	1.4593 29	1.4376 29	1.4671 29	1.4397 29	1.4396 29	1.4393 29	1.4393 29	1.4388 29	1.4374 29			1.4506 29	1.4370 29	1.4333 14	1.4491 29	1.4361 15	1.4329 14
	SVWN		1.4628 29			1.4374 25		1.4392 29
	BLYP	1.4357 27	1.4611 29	1.4369 29	1.4679 29	1.4408 29	1.4397 29	1.4391 29	1.4390 29	1.4379 29	1.4370 28			1.4517 29	1.4356 29		1.4509 13
	B1B95	1.4186 29	1.4321 29	1.4204 29	1.4473 29	1.4218 29	1.4228 29	1.4223 29	1.4231 29	1.4229 29	1.4216 29			1.4346 29	1.4213 29	1.4177 15	1.4327 29	1.4197 15	1.4172 15
	B3LYP	1.4233 29	1.4471 29	1.4242 29	1.4533 29	1.4273 29	1.4270 29	1.4265 29	1.4265 29	1.4242 15	1.4251 28	1.4222 13	1.4297 29	1.4393 29	1.4247 29	1.4216 29	1.4374 29	1.4239 29	1.4211 29	1.4177 17	1.4340 3	1.4187 3
	B3LYPultrafine					1.4274 29		1.4355 5
	B3PW91	1.4266 16	1.4469 29	1.4242 29	1.4512 29	1.4257 29	1.4259 29	1.4255 29	1.4268 29	1.4247 15	1.4248 28			1.4379 29	1.4258 29		1.4385 13
	mPW1PW91	1.4234 18	1.4436 29	1.4190 16	1.4478 29	1.4227 29	1.4231 29	1.4227 29	1.4243 29	1.4242 29	1.4224 28			1.4353 29	1.4238 29		1.4359 13
	M06-2X					1.4184 29
	PBEPBE	1.4388 16	1.4614 29	1.4348 16	1.4617 16	1.4396 29	1.4393 29	1.4388 29	1.4401 29	1.4391 29	1.4376 28	1.4371 11		1.4509 29	1.4379 29	1.4334 15	1.4543 1	1.4393 15	1.4328 15	1.4401 1
	PBEPBEultrafine					1.4427 14
	HSEh1PBE					1.4251 29
Moller Plesset perturbation	MP2FC	1.4148 16	1.4401 29	1.4129 29	1.4471 29	1.4152 28	1.4065 28	1.4061 28	1.4170 29	1.4097 28	1.4132 23		1.4172 29	1.4268 29	1.4143 28	1.4104 12	1.4286 29	1.4127 28	1.4056 8	1.4083 17	1.4228 3	1.4090 3
	MP2FU	1.4147 16	1.4403 29	1.4109 16	1.4432 16	1.4152 28	1.4056 28	1.4050 28	1.4173 29	1.4050 14	1.4091 15			1.4253 29	1.4093 16	1.4053 12	1.4325 8	1.4006 12	1.3978 7	1.4043 17	1.4221 3	1.4065 3
	ROMP2	1.4173 8	1.4382 8	1.4123 8	1.4429 7	1.4130 7	1.4043 7	1.4037 7	1.4177 8	1.4241 5	1.4092 7			1.4274 8	1.4111 7	1.4084 7	1.4248 7	1.4111 7	1.4086 7
	MP3					1.4209 29
	MP4	1.4199 1	1.4480 21			1.4238 28			1.4294 14	1.4128 15					1.4201 26
	B2PLYP					1.4209 29		1.4177 29
Configuration interaction	CID		1.4424 15	1.4139 15	1.4494 15	1.4202 29			1.4207 29						1.4160 6
Configuration interaction	CISD		1.4472 21	1.4148 15	1.4508 15	1.4209 29			1.4200 15						1.4167 6
Quadratic configuration interaction	QCISD	1.4224 1	1.4534 29	1.4317 22	1.4533 16	1.4256 29	1.4116 22	1.4110 28	1.4266 29	1.4160 24	1.4149 15			1.4316 29	1.4182 22					1.4224 2
Quadratic configuration interaction	QCISD(T)					1.4273 29	1.4164 6	1.4161 6	1.4321 14					1.4325 21	1.4200 21		1.4333 15	1.4192 11
Coupled Cluster	CCD	1.4219 1	1.4492 22	1.4172 16	1.4535 16	1.4244 29	1.4102 22	1.4096 22	1.4258 29	1.4114 15	1.4142 15			1.4305 29	1.4176 22		1.4292 15	1.4164 11			1.4272 3	1.4130 3
	CCSD					1.4253 29	1.4152 6	1.4149 6	1.4921 14					1.4332 6	1.4197 6
	CCSD(T)		1.4730 1			1.4261 18	1.4175 14	1.4161 6	1.4319 14	1.4264 1		1.4259 1		1.4325 21	1.4199 21	1.4006 5	1.4332 15	1.4191 11	1.3951 4	1.4138 13	1.4301 3	1.4157 3
	CCSD(T)=FULL					1.4239 9								1.4293 3	1.4143 3	1.3952 5			1.4182 1	1.4200 1	1.4294 3	1.4134 3

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	1.4399 29	1.4224 29	1.4399 29	1.4231 29	1.4260 29	1.4224 29
density functional	B1B95	1.4700 14	1.4464 14
density functional	B3LYP	1.4661 29	1.4442 29	1.4664 29	1.4438 29	1.4522 29	1.4455 29
Moller Plesset perturbation	MP2FC	1.4609 29	1.4383 29	1.4597 29	1.4373 29	1.4432 29	1.4388 29

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.