CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	C2H	¹A_g

Energy calculated at mPW1PW91/3-21G*

	hartrees
Energy at 0K	-235.751296
Energy at 298.15K	-235.766448
Nuclear repulsion energy	262.414173

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at mPW1PW91/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3158	2999	0.00
2	A_g	3136	2978	0.00
3	A_g	3067	2912	0.00
4	A_g	3043	2890	0.00
5	A_g	1591	1511	0.00
6	A_g	1568	1489	0.00
7	A_g	1472	1398	0.00
8	A_g	1394	1323	0.00
9	A_g	1249	1186	0.00
10	A_g	1222	1160	0.00
11	A_g	967	918	0.00
12	A_g	774	735	0.00
13	A_g	504	479	0.00
14	A_g	390	371	0.00
15	A_g	241	228	0.00
16	A_u	3157	2998	48.45
17	A_u	3129	2972	1.03
18	A_u	3063	2908	36.27
19	A_u	1571	1492	8.79
20	A_u	1546	1468	2.09
21	A_u	1450	1377	26.57
22	A_u	1369	1300	2.37
23	A_u	1100	1045	3.46
24	A_u	1004	953	0.05
25	A_u	965	917	5.87
26	A_u	307	291	0.00
27	A_u	201	191	0.04
28	A_u	59	56	0.01
29	B_g	3143	2985	0.00
30	B_g	3130	2972	0.00
31	B_g	3061	2907	0.00
32	B_g	1556	1478	0.00
33	B_g	1550	1472	0.00
34	B_g	1441	1369	0.00
35	B_g	1382	1312	0.00
36	B_g	1193	1133	0.00
37	B_g	989	940	0.00
38	B_g	955	907	0.00
39	B_g	436	414	0.00
40	B_g	204	194	0.00
41	B_u	3147	2988	64.19
42	B_u	3138	2980	113.64
43	B_u	3066	2911	56.71
44	B_u	3057	2903	7.08
45	B_u	1575	1496	30.81
46	B_u	1567	1488	21.46
47	B_u	1462	1388	27.76
48	B_u	1344	1276	3.39
49	B_u	1209	1148	12.52
50	B_u	1040	988	17.02
51	B_u	880	836	3.64
52	B_u	414	393	0.57
53	B_u	353	335	0.33
54	B_u	217	206	0.02

Unscaled Zero Point Vibrational Energy (zpe) 42102.1 cm^-1
Scaled (by 0.9496) Zero Point Vibrational Energy (zpe) 39980.2 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at mPW1PW91/3-21G*

A	B	C
0.14069	0.09633	0.06275

See section I.F.4 to change rotational constant units

Geometric Data calculated at mPW1PW91/3-21G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.774	0.000
C2	0.000	-0.774	0.000
H3	-1.050	1.104	0.000
H4	1.050	-1.104	0.000
C5	0.698	1.338	1.250
C6	0.698	1.338	-1.250
C7	-0.698	-1.338	1.250
C8	-0.698	-1.338	-1.250
H9	1.726	0.960	1.306
H10	1.726	0.960	-1.306
H11	-1.726	-0.960	1.306
H12	-1.726	-0.960	-1.306
H13	0.740	2.432	1.200
H14	0.176	1.063	2.170
H15	0.740	2.432	-1.200
H16	0.176	1.063	-2.170
H17	-0.740	-2.432	1.200
H18	-0.176	-1.063	2.170
H19	-0.740	-2.432	-1.200
H20	-0.176	-1.063	-2.170

Atom - Atom Distances (Å)

	C1	C2	H3	H4	C5	C6	C7	C8	H9	H10	H11	H12	H13	H14	H15	H16	H17	H18	H19	H20
C1		1.5479	1.1003	2.1516	1.5391	1.5391	2.5519	2.5519	2.1725	2.1725	2.7736	2.7736	2.1766	2.1967	2.1766	2.1967	3.5024	2.8489	3.5024	2.8489
C2	1.5479		2.1516	1.1003	2.5519	2.5519	1.5391	1.5391	2.7736	2.7736	2.1725	2.1725	3.5024	2.8489	3.5024	2.8489	2.1766	2.1967	2.1766	2.1967
H3	1.1003	2.1516		3.0469	2.1615	2.1615	2.7665	2.7665	3.0710	3.0710	2.5348	2.5348	2.5309	2.4930	2.5309	2.4930	3.7474	3.1891	3.7474	3.1891
H4	2.1516	1.1003	3.0469		2.7665	2.7665	2.1615	2.1615	2.5348	2.5348	3.0710	3.0710	3.7474	3.1891	3.7474	3.1891	2.5309	2.4930	2.5309	2.4930
C5	1.5391	2.5519	2.1615	2.7665		2.5002	3.0192	3.9200	1.0970	2.7807	3.3415	4.2065	1.0956	1.0934	2.6837	3.4712	4.0358	2.7163	4.7211	4.2698
C6	1.5391	2.5519	2.1615	2.7665	2.5002		3.9200	3.0192	2.7807	1.0970	4.2065	3.3415	2.6837	3.4712	1.0956	1.0934	4.7211	4.2698	4.0358	2.7163
C7	2.5519	1.5391	2.7665	2.1615	3.0192	3.9200		2.5002	3.3415	4.2065	1.0970	2.7807	4.0358	2.7163	4.7211	4.2698	1.0956	1.0934	2.6837	3.4712
C8	2.5519	1.5391	2.7665	2.1615	3.9200	3.0192	2.5002		4.2065	3.3415	2.7807	1.0970	4.7211	4.2698	4.0358	2.7163	2.6837	3.4712	1.0956	1.0934
H9	2.1725	2.7736	3.0710	2.5348	1.0970	2.7807	3.3415	4.2065		2.6114	3.9509	4.7359	1.7751	1.7781	3.0691	3.8075	4.1954	2.9088	4.8857	4.4493
H10	2.1725	2.7736	3.0710	2.5348	2.7807	1.0970	4.2065	3.3415	2.6114		4.7359	3.9509	3.0691	3.8075	1.7751	1.7781	4.8857	4.4493	4.1954	2.9088
H11	2.7736	2.1725	2.5348	3.0710	3.3415	4.2065	1.0970	2.7807	3.9509	4.7359		2.6114	4.1954	2.9088	4.8857	4.4493	1.7751	1.7781	3.0691	3.8075
H12	2.7736	2.1725	2.5348	3.0710	4.2065	3.3415	2.7807	1.0970	4.7359	3.9509	2.6114		4.8857	4.4493	4.1954	2.9088	3.0691	3.8075	1.7751	1.7781
H13	2.1766	3.5024	2.5309	3.7474	1.0956	2.6837	4.0358	4.7211	1.7751	3.0691	4.1954	4.8857		1.7703	2.4004	3.6816	5.0843	3.7411	5.6225	4.9413
H14	2.1967	2.8489	2.4930	3.1891	1.0934	3.4712	2.7163	4.2698	1.7781	3.8075	2.9088	4.4493	1.7703		3.6816	4.3410	3.7411	2.1548	4.9413	4.8464
H15	2.1766	3.5024	2.5309	3.7474	2.6837	1.0956	4.7211	4.0358	3.0691	1.7751	4.8857	4.1954	2.4004	3.6816		1.7703	5.6225	4.9413	5.0843	3.7411
H16	2.1967	2.8489	2.4930	3.1891	3.4712	1.0934	4.2698	2.7163	3.8075	1.7781	4.4493	2.9088	3.6816	4.3410	1.7703		4.9413	4.8464	3.7411	2.1548
H17	3.5024	2.1766	3.7474	2.5309	4.0358	4.7211	1.0956	2.6837	4.1954	4.8857	1.7751	3.0691	5.0843	3.7411	5.6225	4.9413		1.7703	2.4004	3.6816
H18	2.8489	2.1967	3.1891	2.4930	2.7163	4.2698	1.0934	3.4712	2.9088	4.4493	1.7781	3.8075	3.7411	2.1548	4.9413	4.8464	1.7703		3.6816	4.3410
H19	3.5024	2.1766	3.7474	2.5309	4.7211	4.0358	2.6837	1.0956	4.8857	4.1954	3.0691	1.7751	5.6225	4.9413	5.0843	3.7411	2.4004	3.6816		1.7703
H20	2.8489	2.1967	3.1891	2.4930	4.2698	2.7163	3.4712	1.0934	4.4493	2.9088	3.8075	1.7781	4.9413	4.8464	3.7411	2.1548	3.6816	4.3410	1.7703

picture of Butane, 2,3-dimethyl- state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H4	107.472	C1	C2	C7	111.517
C1	C2	C8	111.517	C1	C5	H9	109.868
C1	C5	H13	110.266	C1	C5	H14	112.009
C1	C6	H10	109.868	C1	C6	H15	110.266
C1	C6	H16	112.009	C2	C1	H3	107.472
C2	C1	C5	111.517	C2	C1	C6	111.517
C2	C7	H11	109.868	C2	C7	H17	110.266
C2	C7	H18	112.009	C2	C8	H12	109.868
C2	C8	H19	110.266	C2	C8	H20	112.009
H3	C1	C5	108.817	H3	C1	C6	108.817
H4	C2	C7	108.817	H4	C2	C8	108.817
C5	C1	C6	108.629	C7	C2	C8	108.629
H9	C5	H13	108.108	H9	C5	H14	108.539
H10	C6	H15	108.108	H10	C6	H16	108.539
H11	C7	H17	108.108	H11	C7	H18	108.539
H12	C8	H19	108.108	H12	C8	H20	108.539
H13	C5	H14	107.942	H15	C6	H16	107.942
H17	C7	H18	107.942	H19	C8	H20	107.942

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G* Charges (e)

Number	Element	Mulliken
1	C	-0.265
2	C	-0.265
3	H	0.210
4	H	0.210
5	C	-0.600
6	C	-0.600
7	C	-0.600
8	C	-0.600
9	H	0.206
10	H	0.206
11	H	0.206
12	H	0.206
13	H	0.208
14	H	0.213
15	H	0.208
16	H	0.213
17	H	0.208
18	H	0.213
19	H	0.208
20	H	0.213

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.000	0.000	0.000	0.000
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-41.126	-0.219	0.000
y	-0.219	-41.366	0.000
z	0.000	0.000	-41.642

Traceless
	x	y	z
x	0.378	-0.219	0.000
y	-0.219	0.018	0.000
z	0.000	0.000	-0.396

Polar
3z²-r²	-0.792
x²-y²	0.240
xy	-0.219
xz	0.000
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	8.079	0.178	0.000
y	0.178	9.761	0.000
z	0.000	0.000	9.144

<r²> (average value of r²) Å²

<r²>	207.405
(<r²>)^1/2	14.402

All results from a given calculation for C₆H₁₄ (Butane, 2,3-dimethyl-)

using model chemistry: mPW1PW91/3-21G*

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
	Home All data for one species Geometry Experimental Experimental Geometries Same bond/angle many molecules Internal Coordinates by type Bond angles Calculated Calculated geometry Rotational constant Moments of inertia Products of moments of inertia BSE Bond lengths Show me a calculated geometry Comparisons Bonds, angles Rotational Constants Products of moments of inertia Point group Bad Calculations Bad moment of inertia Tutorials and Explanations Angle formulas Vibrations Experimental Vibrational frequencies Calculated Frequencies Scale factors Reactions Entropies Ions List Ions Energy Calculated Ionization Energy Compare Ionzation energy Electron Affinity Calculated Electron affinity Compare Electron affinity Proton Affinity Calculated Proton affinity Compare Proton affinity Ionization changes point group Experimental One molecule all properties One property a few molecules Enthalpy of formation Entropy Integrated Heat Capacity Heat Capacity Rotational Constants Vibrational Frequencies Dipole moment Ionization Energy Polarizability Quadrupole Point Groups Geometry Experimental Geometries Internal Coordinates by type Bond angles Rotational Constants Point Groups Diatomic bond lengths Vibrations Vibrational frequencies Diatomic Triatomics Energy Atomization Energy Internal Rotation Electrostatics Dipole Quadrupole Polarizability Reference Data Reference states Spin Splittings Molecules with good enthalpy Enthalpy at 0 Kelvin Calculated Energy Optimized Energy Energy 298K Minimum conformation Hydrogen bonds H bond with counterpoise Reaction Reaction Energy 0K Reaction Energy 298K Internal Rotation Barriers to internal rotation Rotational barrier and dipole Rotational Barrier 2 molecules Orbital HOMO LUMO gap HOMO Orbital Energies Nuclear repulsion energy Correlation Full vs Frozen core energies Partial correlation energies Ion Calculated Ionization Energy Vertical ionization Energy Calculated Electron affinity Calculated Proton affinity Atom charge differences Excited State Singlet triplet gap Electronic state Transition state Basis Set Extrapolation BSE energy BSE Bond lengths Geometry Calculated geometry AIM bond orders One type of bond Rotation Rotational constant Products of moments of inertia Moments of inertia Inertial defects Second moments Point group State symmetry <r2> Sorted by r2 Z-matrix Bad Calculations Bad moment of inertia Bad Calculated Bond Lengths Bad point group Worst molecules Vibrations Frequencies Animated vibrations Anharmonic Zero point energy (ZPE) Scale Factors Scale factors Scale factor uncertainty Calculate a scale factor Why scale vibrations Set scaling factors Bad Calculations Bad Vib. HF vs MP2 Bad vib. Calc. vs exp. Big anharmonicity Electrostatics Charges Mulliken CHELP Aim ESP Dipole Dipole Dipole angle Dipole calculation types Quadrupole Polarizability Spin Spin density Entropy and Heat Capacity Entropy Reaction entropy Heat Capacity Reaction Reaction Energy 0K Reaction Energy 298K Isodesmic reactions Transition State Transition state Transition state frequencies Transition state geometries IRC Lookup by property By frequency Comparisons Geometry Bonds, angles Bond, angle, or dihedral DFT grid size on point group DFT grid on bond length Core correlation - bond length Same bond/angle many molecules Isoelectronic diatomics Isoelectronic triatomic angles Average bond lengths Rotation Rotational Constants Products of moments of inertia Point group Vibrations Vibrations 2 calculations Frequency differences One frequency Zero point energy Intensity Intensity for one mode Vibrational intensities Reduced mass comparison Anharmonic Triatomic Scale factors Energy Reaction Reaction Energy 0K Reaction Energy 298K Atomization 0K Atomization 298K Single point vs optimized DFT grid size on energy Semiempirical enthalpy Internal rotation Similar molecules Conformation Sets of isomers Sets of tautomers Isomers Entropy Entropy Heat capacity Entropy of several molecules Integrated heat capacity Reaction entropy Electrostatics Dipole Polarizability Several molecules Quadrupole Ion Compare Ionzation energy Koopman ionization energy Koopman IE for a few molecules Compare Electron affinity Compare Proton affinity Protonation Site Resources Info on Results Calculations Done Method and basis set List molecules One molecule Multiple conformers, states Multiple conformers, states Basis functions used I/O files Input/output files MOL file Z-matrix wfn files Glossary Conversion Forms B to I, I to B Angle formulas Integrated heat Capacity Calculating Enthalpy Links NIST Links NIST webbook bibliographic data CCCBDB Experimental data External links Basis Set Exchange Computational Chemistry List Thermochemistry in Gaussian Minnesota Database Collection Benchmark Energy and Geometry Point Groups Thermochemistry Thermochemistry Molecules with good enthalpy A → B + C Reference states Tutorials Vibrations Why scale vibrations Zero-point energies Entropy Methyl rotor entropy Entropy and conformations Energy Getting enthalpy of formation Vertical vs adiabatic IE Thermo from calculations Electrostatics Dipole parts by point group Quadrupoles Geometry Angle formulas Cost Cost Comparison Timings Comparison Bad Calculations Geometry Bad moment of inertia Bad Calculated Bond Lengths Bad point group Worst molecules Vibrations Bad vib. Calc. vs exp. Bad Vib. HF vs MP2 Bad scale factors Low excited states Oddities NaCN Is not linear FAQ Help Units Choose Units Energy Bond length Rotational Constant Moment of Inertia Dipole and Quadrupole Polarizability Explanations Hartree cm-1 Debye Credits Just show me Show me a calculated geometry Summary Using older interface Limit Basis sets Method options List Recent molecules Choose a few Molecules Number of atoms By heavy atoms Diatomics InChI Deuterated Dimers Geometry Point group Point group count Bonds types Isodesmic reactions Bad point group Multiple conformers, states Vibrations Big anharmonicity Energy Enthalpy at 0 Kelvin Similar molecules Similar Isomers Cis/trans Tautomers Multiple conformers, states Ions, Dipoles, etc. List Ions Ionization changes point group Dipole Quadrupole Polarizability Proton Affinities Index of CCCBDB Feedback Error form Wants
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for C6H14 (Butane, 2,3-dimethyl-)

using model chemistry: mPW1PW91/3-21G*

States and conformations

All results from a given calculation for C₆H₁₄ (Butane, 2,3-dimethyl-)