CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	C2	¹A^'

Energy calculated at CCSD(T)/6-31G*

	hartrees
Energy at 0K	-235.058905
Energy at 298.15K	-235.071185
HF Energy	-234.174609
Nuclear repulsion energy	242.854472

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 CCSD(T)/6-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	A'	3227	3105
2	A'	3148	3028
3	A'	3133	3014
4	A'	3127	3008
5	A'	3121	3003
6	A'	3049	2934
7	A'	3044	2928
8	A'	3030	2915
9	A'	1719	1654
10	A'	1553	1494
11	A'	1550	1491
12	A'	1539	1480
13	A'	1485	1428
14	A'	1460	1404
15	A'	1450	1395
16	A'	1372	1320
17	A'	1338	1287
18	A'	1218	1172
19	A'	1131	1088
20	A'	1026	987
21	A'	989	952
22	A'	920	885
23	A'	743	714
24	A'	527	507
25	A'	445	428
26	A'	335	322
27	A'	285	275
28	A'	265	255
29	A"	3125	3007
30	A"	3118	3000
31	A"	3106	2989
32	A"	3043	2928
33	A"	1543	1485
34	A"	1532	1474
35	A"	1522	1465
36	A"	1438	1383
37	A"	1378	1325
38	A"	1155	1111
39	A"	1084	1043
40	A"	987	949
41	A"	944	909
42	A"	890	857
43	A"	737	709
44	A"	547	526
45	A"	273	263
46	A"	214	206
47	A"	163	157
48	A"	28	27

Unscaled Zero Point Vibrational Energy (zpe) 36526.8 cm^-1
Scaled (by 0.9621) Zero Point Vibrational Energy (zpe) 35142.4 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 CCSD(T)/6-31G*

A	B	C
0.14673	0.08279	0.08180

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

Geometric Data calculated at CCSD(T)/6-31G*

Point Group is C_s

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.959	-1.823	0.000
C2	-0.063	-0.818	0.000
C3	-0.520	0.634	0.000
C4	1.425	-1.095	0.000
C5	-0.063	1.379	1.265
C6	-0.063	1.379	-1.265
H7	-0.651	-2.869	0.000
H8	-2.033	-1.632	0.000
H9	-1.622	0.622	0.000
H10	1.618	-2.175	0.000
H11	1.915	-0.663	-0.884
H12	1.915	-0.663	0.884
H13	-0.493	2.391	1.290
H14	-0.381	0.847	2.172
H15	1.031	1.482	1.293
H16	-0.493	2.391	-1.290
H17	-0.381	0.847	-2.172
H18	1.031	1.482	-1.293

Atom - Atom Distances (Å)

	C1	C2	C3	C4	C5	C6	H7	H8	H9	H10	H11	H12	H13	H14	H15	H16	H17	H18
C1		1.3467	2.4953	2.4928	3.5575	3.5575	1.0908	1.0907	2.5330	2.6011	3.2230	3.2230	4.4309	3.4898	4.0688	4.4309	3.4898	4.0688
C2	1.3467		1.5217	1.5135	2.5350	2.5350	2.1341	2.1321	2.1224	2.1605	2.1720	2.1720	3.4844	2.7549	2.8562	3.4844	2.7549	2.8562
C3	2.4953	1.5217		2.6023	1.5378	1.5378	3.5052	2.7247	1.1024	3.5299	2.8971	2.8971	2.1797	2.1865	2.1904	2.1797	2.1865	2.1904
C4	2.4928	1.5135	2.6023		3.1520	3.1520	2.7309	3.4997	3.4978	1.0972	1.0995	1.0995	4.1821	3.4279	2.9102	4.1821	3.4279	2.9102
C5	3.5575	2.5350	1.5378	3.1520		2.5298	4.4715	3.8146	2.1462	4.1302	3.5639	2.8683	1.0992	1.0985	1.0990	2.7810	3.4921	2.7839
C6	3.5575	2.5350	1.5378	3.1520	2.5298		4.4715	3.8146	2.1462	4.1302	2.8683	3.5639	2.7810	3.4921	2.7839	1.0992	1.0985	1.0990
H7	1.0908	2.1341	3.5052	2.7309	4.4715	4.4715		1.8547	3.6236	2.3728	3.4977	3.4977	5.4179	4.3127	4.8410	5.4179	4.3127	4.8410
H8	1.0907	2.1321	2.7247	3.4997	3.8146	3.8146	1.8547		2.2912	3.6912	4.1604	4.1604	4.4967	3.6868	4.5564	4.4967	3.6868	4.5564
H9	2.5330	2.1224	1.1024	3.4978	2.1462	2.1462	3.6236	2.2912		4.2806	3.8660	3.8660	2.4634	2.5115	3.0746	2.4634	2.5115	3.0746
H10	2.6011	2.1605	3.5299	1.0972	4.1302	4.1302	2.3728	3.6912	4.2806		1.7768	1.7768	5.1927	4.2246	3.9234	5.1927	4.2246	3.9234
H11	3.2230	2.1720	2.8971	1.0995	3.5639	2.8683	3.4977	4.1604	3.8660	1.7768		1.7688	4.4551	4.1101	3.1820	3.9096	3.0348	2.3559
H12	3.2230	2.1720	2.8971	1.0995	2.8683	3.5639	3.4977	4.1604	3.8660	1.7768	1.7688		3.9096	3.0348	2.3559	4.4551	4.1101	3.1820
H13	4.4309	3.4844	2.1797	4.1821	1.0992	2.7810	5.4179	4.4967	2.4634	5.1927	4.4551	3.9096		1.7811	1.7739	2.5795	3.7916	3.1333
H14	3.4898	2.7549	2.1865	3.4279	1.0985	3.4921	4.3127	3.6868	2.5115	4.2246	4.1101	3.0348	1.7811		1.7803	3.7916	4.3433	3.7950
H15	4.0688	2.8562	2.1904	2.9102	1.0990	2.7839	4.8410	4.5564	3.0746	3.9234	3.1820	2.3559	1.7739	1.7803		3.1333	3.7950	2.5862
H16	4.4309	3.4844	2.1797	4.1821	2.7810	1.0992	5.4179	4.4967	2.4634	5.1927	3.9096	4.4551	2.5795	3.7916	3.1333		1.7811	1.7739
H17	3.4898	2.7549	2.1865	3.4279	3.4921	1.0985	4.3127	3.6868	2.5115	4.2246	3.0348	4.1101	3.7916	4.3433	3.7950	1.7811		1.7803
H18	4.0688	2.8562	2.1904	2.9102	2.7839	1.0990	4.8410	4.5564	3.0746	3.9234	2.3559	3.1820	3.1333	3.7950	2.5862	1.7739	1.7803

picture of 2,3-dimethylbut-1-ene state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C3	120.784	C1	C2	C4	121.172
C2	C1	H7	121.866	C2	C1	H8	121.671
C2	C3	C5	111.904	C2	C3	C6	111.904
C2	C3	H9	106.873	C2	C4	H10	110.686
C2	C4	H11	111.474	C2	C4	H12	111.474
C3	C2	C4	118.045	C3	C5	H13	110.387
C3	C5	H14	110.973	C3	C5	H15	111.253
C3	C6	H16	110.387	C3	C6	H17	110.973
C3	C6	H18	111.253	C5	C3	C6	110.676
C5	C3	H9	107.610	C6	C3	H9	107.610
H7	C1	H8	116.463	H10	C4	H11	107.966
H10	C4	H12	107.966	H11	C4	H12	107.101
H13	C5	H14	108.279	H13	C5	H15	107.601
H14	C5	H15	108.225	H16	C6	H17	108.279
H16	C6	H18	107.601	H17	C6	H18	108.225

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for C₆H₁₂ (2,3-dimethylbut-1-ene)

using model chemistry: CCSD(T)/6-31G*

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 C6H12 (2,3-dimethylbut-1-ene)

using model chemistry: CCSD(T)/6-31G*

States and conformations

All results from a given calculation for C₆H₁₂ (2,3-dimethylbut-1-ene)