III.G.1.a.

Comparison of levels of theory for K-Br

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	PM6	2.9960 1
composite	G2	2.8947 1

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
hartree fock	HF		2.9977 1	2.8809 1	2.9666 1	2.8941 1	2.8947 1	2.9302 1	2.9120 1	2.9120 1	2.8920 1	2.9130 1	2.9918 1
density functional	LSDA	2.7363 1	2.9006 1	2.7667 1	2.8698 1	2.7827 1	2.7827 1	2.8151 1	2.7573 1	2.7573 1	2.7593 1
	SVWN		2.9006 1			2.7827 1		2.8148 1
	BLYP		2.9883 1	2.8515 1	2.9513 1	2.8684 1	2.8684 1	2.9072 1	2.8572 1	2.8572 1	2.8483 1
	B1B95					2.8376 1
	B3LYP		2.9674 1	2.8388 1	2.9332 1	2.8526 1	2.8526 1	2.8891 1	2.8475 1	2.8475 1	2.8363 1		2.9618 1
	B3LYPultrafine					2.8525 1
	B3PW91		2.9629 1	2.8354 1	2.9268 1	2.8439 1	2.8439 1	2.8769 1	2.8345 1	2.8345 1	2.8272 1
	mPW1PW91		2.9545 1	2.8294 1		2.8390 1	2.8390 1	2.8725 1	2.8307 1	2.8307 1	2.8230 1
	M06-2X					2.8343 1
	PBEPBE		2.9664 1	2.8330 1	2.9309 1	2.8459 1	2.8459 1	2.8811 1	2.8287 1	2.8287 1	2.8261 1
	PBEPBEultrafine					2.8461 1
	HSEh1PBE					2.8371 1
Moller Plesset perturbation	MP2FC		3.0156 1	2.9076 1	2.9794 1	2.8682 1	2.8682 1	2.9056 1	2.8532 1	2.8532 1	2.8363 1		3.0127 1
	MP2FU		3.0112 1	2.8752 1	2.9793 1	2.8651 1	2.8651 1	2.9027 1	2.8472 1
	MP3					2.8699 1
	MP4		3.0205 1			2.8685 1
	B2PLYP					2.8539 1		2.8908 1
Configuration interaction	CID		3.0168 1	2.9066 1	2.9797 1	2.8718 1			2.8685 1
Configuration interaction	CISD		3.0184 1	2.9068 1	2.9808 1	2.8713 1			2.8684 1
Quadratic configuration interaction	QCISD		3.0202 1	2.9097 1	2.9822 1	2.8697 1	2.8697 1	2.9069 1	2.8636 1
Quadratic configuration interaction	QCISD(T)					2.8687 1
Coupled Cluster	CCD		3.0177 1	2.9090 1	2.9806 1	2.8702 1	2.8702 1	2.9072 1	2.8633 1
	CCSD					2.8698 1
	CCSD(T)					2.8683 1
	CCSD(T)=FULL					2.8653 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	3.0739 1		3.0739 1		3.0146 1	3.0306 1
density functional	B1B95	3.0529 1
density functional	B3LYP	3.0694 1		3.0694 1		2.9821 1	2.9984 1
Moller Plesset perturbation	MP2FC	3.0909 1		3.0909 1		3.0167 1	3.0384 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.