CCCBDB calculation results Page

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

Energy calculated at G2

	hartrees
Energy at 0K	-314.983053
Energy at 298.15K	-315.003704
Nuclear repulsion energy	375.003678

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 HF/6-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3258	3069	0.00
2	A_g	3196	3012	0.00
3	A_g	3188	3004	0.00
4	A_g	3180	2997	0.00
5	A_g	3174	2991	0.00
6	A_g	1656	1560	0.00
7	A_g	1643	1548	0.00
8	A_g	1636	1542	0.00
9	A_g	1633	1539	0.00
10	A_g	1571	1480	0.00
11	A_g	1567	1476	0.00
12	A_g	1530	1441	0.00
13	A_g	1428	1346	0.00
14	A_g	1255	1182	0.00
15	A_g	1142	1076	0.00
16	A_g	1126	1060	0.00
17	A_g	1084	1022	0.00
18	A_g	972	916	0.00
19	A_g	506	476	0.00
20	A_g	291	274	0.00
21	A_g	210	198	0.00
22	A_u	3258	3070	253.37
23	A_u	3237	3050	122.56
24	A_u	3212	3026	1.78
25	A_u	3193	3008	0.07
26	A_u	1644	1549	9.81
27	A_u	1463	1379	0.47
28	A_u	1439	1356	0.59
29	A_u	1352	1274	0.01
30	A_u	1124	1059	0.10
31	A_u	954	899	0.40
32	A_u	812	765	0.69
33	A_u	781	736	2.94
34	A_u	265	250	0.00
35	A_u	171	161	0.00
36	A_u	74	70	0.00
37	A_u	52	49	0.01
38	B_g	3258	3069	0.00
39	B_g	3225	3038	0.00
40	B_g	3200	3015	0.00
41	B_g	3191	3007	0.00
42	B_g	1644	1549	0.00
43	B_g	1464	1379	0.00
44	B_g	1450	1366	0.00
45	B_g	1399	1319	0.00
46	B_g	1321	1245	0.00
47	B_g	1044	984	0.00
48	B_g	871	820	0.00
49	B_g	786	741	0.00
50	B_g	268	252	0.00
51	B_g	146	138	0.00
52	B_g	119	112	0.00
53	B_u	3258	3069	129.26
54	B_u	3196	3011	70.73
55	B_u	3192	3007	233.10
56	B_u	3181	2998	7.95
57	B_u	3174	2990	1.61
58	B_u	1660	1564	4.27
59	B_u	1650	1555	0.87
60	B_u	1637	1542	0.70
61	B_u	1633	1539	0.29
62	B_u	1568	1477	3.17
63	B_u	1558	1468	0.34
64	B_u	1484	1398	2.67
65	B_u	1368	1289	5.48
66	B_u	1195	1126	2.54
67	B_u	1141	1075	0.21
68	B_u	1082	1020	0.31
69	B_u	959	903	1.97
70	B_u	501	472	0.14
71	B_u	363	342	0.02
72	B_u	85	80	0.00

Unscaled Zero Point Vibrational Energy (zpe) 57772.8 cm^-1
Scaled (by 0.9422) Zero Point Vibrational Energy (zpe) 54433.5 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 MP2=FULL/6-31G*

A	B	C
0.35838	0.01642	0.01608

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

Geometric Data calculated at MP2=FULL/6-31G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.001	0.763	0.000
C2	-0.001	-0.763	0.000
C3	-1.400	1.367	0.000
C4	1.400	-1.367	0.000
C5	-1.400	2.892	0.000
C6	1.400	-2.892	0.000
C7	-2.805	3.483	0.000
C8	2.805	-3.483	0.000
H9	0.552	1.125	0.878
H10	0.552	1.125	-0.878
H11	-0.552	-1.125	0.878
H12	-0.552	-1.125	-0.878
H13	-1.951	1.005	-0.878
H14	-1.951	1.005	0.878
H15	1.951	-1.005	-0.878
H16	1.951	-1.005	0.878
H17	-0.849	3.251	0.878
H18	-0.849	3.251	-0.878
H19	0.849	-3.251	0.878
H20	0.849	-3.251	-0.878
H21	-2.780	4.577	0.000
H22	-3.364	3.160	-0.884
H23	-3.364	3.160	0.884
H24	2.780	-4.577	0.000
H25	3.364	-3.160	-0.884
H26	3.364	-3.160	0.884

Atom - Atom Distances (Å)

	C1	C2	C3	C4	C5	C6	C7	C8	H9	H10	H11	H12	H13	H14	H15	H16	H17	H18	H19	H20	H21	H22	H23	H24	H25	H26
C1		1.5255	1.5253	2.5477	2.5484	3.9131	3.9081	5.0884	1.0982	1.0982	2.1539	2.1539	2.1542	2.1542	2.7748	2.7748	2.7722	2.7722	4.1954	4.1954	4.7204	4.2248	4.2248	6.0196	5.2420	5.2420
C2	1.5255		2.5477	1.5253	3.9131	2.5484	5.0884	3.9081	2.1539	2.1539	1.0982	1.0982	2.7748	2.7748	2.1542	2.1542	4.1954	4.1954	2.7722	2.7722	6.0196	5.2420	5.2420	4.7204	4.2248	4.2248
C3	1.5253	2.5477		3.9125	1.5252	5.0962	2.5407	6.4188	2.1538	2.1538	2.7743	2.7743	1.0983	1.0983	4.1981	4.1981	2.1510	2.1510	5.2106	5.2106	3.4945	2.8026	2.8026	7.2661	6.6305	6.6305
C4	2.5477	1.5253	3.9125		5.0962	1.5252	6.4188	2.5407	2.7743	2.7743	2.1538	2.1538	4.1981	4.1981	1.0983	1.0983	5.2106	5.2106	2.1510	2.1510	7.2661	6.6305	6.6305	3.4945	2.8026	2.8026
C5	2.5484	3.9131	1.5252	5.0962		6.4255	1.5245	7.6368	2.7755	2.7755	4.1978	4.1978	2.1531	2.1531	5.2138	5.2138	1.0970	1.0970	6.6002	6.6002	2.1783	2.1701	2.1701	8.5588	7.7523	7.7523
C6	3.9131	2.5484	5.0962	1.5252	6.4255		7.6368	1.5245	4.1978	4.1978	2.7755	2.7755	5.2138	5.2138	2.1531	2.1531	6.6002	6.6002	1.0970	1.0970	8.5588	7.7523	7.7523	2.1783	2.1701	2.1701
C7	3.9081	5.0884	2.5407	6.4188	1.5245	7.6368		8.9444	4.1955	4.1955	5.2039	5.2039	2.7646	2.7646	6.5981	6.5981	2.1567	2.1567	7.7119	7.7119	1.0938	1.0942	1.0942	9.8061	9.1087	9.1087
C8	5.0884	3.9081	6.4188	2.5407	7.6368	1.5245	8.9444		5.2039	5.2039	4.1955	4.1955	6.5981	6.5981	2.7646	2.7646	7.7119	7.7119	2.1567	2.1567	9.8061	9.1087	9.1087	1.0938	1.0942	1.0942
H9	1.0982	2.1539	2.1538	2.7743	2.7755	4.1978	4.1955	5.2039		1.7569	2.5054	3.0600	3.0603	2.5058	3.0950	2.5481	2.5464	3.0932	4.3860	4.7245	4.8777	4.7517	4.4130	6.1842	5.4195	5.1251
H10	1.0982	2.1539	2.1538	2.7743	2.7755	4.1978	4.1955	5.2039	1.7569		3.0600	2.5054	2.5058	3.0603	2.5481	3.0950	3.0932	2.5464	4.7245	4.3860	4.8777	4.4130	4.7517	6.1842	5.1251	5.4195
H11	2.1539	1.0982	2.7743	2.1538	4.1978	2.7755	5.2039	4.1955	2.5054	3.0600		1.7569	3.0950	2.5481	3.0603	2.5058	4.3860	4.7245	2.5464	3.0932	6.1842	5.4195	5.1251	4.8777	4.7517	4.4130
H12	2.1539	1.0982	2.7743	2.1538	4.1978	2.7755	5.2039	4.1955	3.0600	2.5054	1.7569		2.5481	3.0950	2.5058	3.0603	4.7245	4.3860	3.0932	2.5464	6.1842	5.1251	5.4195	4.8777	4.4130	4.7517
H13	2.1542	2.7748	1.0983	4.1981	2.1531	5.2138	2.7646	6.5981	3.0603	2.5058	3.0950	2.5481		1.7567	4.3894	4.7279	3.0571	2.5025	5.3886	5.0945	3.7707	2.5770	3.1218	7.3697	6.7524	6.9785
H14	2.1542	2.7748	1.0983	4.1981	2.1531	5.2138	2.7646	6.5981	2.5058	3.0603	2.5481	3.0950	1.7567		4.7279	4.3894	2.5025	3.0571	5.0945	5.3886	3.7707	3.1218	2.5770	7.3697	6.9785	6.7524
H15	2.7748	2.1542	4.1981	1.0983	5.2138	2.1531	6.5981	2.7646	3.0950	2.5481	3.0603	2.5058	4.3894	4.7279		1.7567	5.3886	5.0945	3.0571	2.5025	7.3697	6.7524	6.9785	3.7707	2.5770	3.1218
H16	2.7748	2.1542	4.1981	1.0983	5.2138	2.1531	6.5981	2.7646	2.5481	3.0950	2.5058	3.0603	4.7279	4.3894	1.7567		5.0945	5.3886	2.5025	3.0571	7.3697	6.9785	6.7524	3.7707	3.1218	2.5770
H17	2.7722	4.1954	2.1510	5.2106	1.0970	6.6002	2.1567	7.7119	2.5464	3.0932	4.3860	4.7245	3.0571	2.5025	5.3886	5.0945		1.7551	6.7206	6.9460	2.5017	3.0717	2.5167	8.6729	7.8710	7.6715
H18	2.7722	4.1954	2.1510	5.2106	1.0970	6.6002	2.1567	7.7119	3.0932	2.5464	4.7245	4.3860	2.5025	3.0571	5.0945	5.3886	1.7551		6.9460	6.7206	2.5017	2.5167	3.0717	8.6729	7.6715	7.8710
H19	4.1954	2.7722	5.2106	2.1510	6.6002	1.0970	7.7119	2.1567	4.3860	4.7245	2.5464	3.0932	5.3886	5.0945	3.0571	2.5025	6.7206	6.9460		1.7551	8.6729	7.8710	7.6715	2.5017	3.0717	2.5167
H20	4.1954	2.7722	5.2106	2.1510	6.6002	1.0970	7.7119	2.1567	4.7245	4.3860	3.0932	2.5464	5.0945	5.3886	2.5025	3.0571	6.9460	6.7206	1.7551		8.6729	7.6715	7.8710	2.5017	2.5167	3.0717
H21	4.7204	6.0196	3.4945	7.2661	2.1783	8.5588	1.0938	9.8061	4.8777	4.8777	6.1842	6.1842	3.7707	3.7707	7.3697	7.3697	2.5017	2.5017	8.6729	8.6729		1.7685	1.7685	10.7102	9.9192	9.9192
H22	4.2248	5.2420	2.8026	6.6305	2.1701	7.7523	1.0942	9.1087	4.7517	4.4130	5.4195	5.1251	2.5770	3.1218	6.7524	6.9785	3.0717	2.5167	7.8710	7.6715	1.7685		1.7672	9.9192	9.2307	9.3983
H23	4.2248	5.2420	2.8026	6.6305	2.1701	7.7523	1.0942	9.1087	4.4130	4.7517	5.1251	5.4195	3.1218	2.5770	6.9785	6.7524	2.5167	3.0717	7.6715	7.8710	1.7685	1.7672		9.9192	9.3983	9.2307
H24	6.0196	4.7204	7.2661	3.4945	8.5588	2.1783	9.8061	1.0938	6.1842	6.1842	4.8777	4.8777	7.3697	7.3697	3.7707	3.7707	8.6729	8.6729	2.5017	2.5017	10.7102	9.9192	9.9192		1.7685	1.7685
H25	5.2420	4.2248	6.6305	2.8026	7.7523	2.1701	9.1087	1.0942	5.4195	5.1251	4.7517	4.4130	6.7524	6.9785	2.5770	3.1218	7.8710	7.6715	3.0717	2.5167	9.9192	9.2307	9.3983	1.7685		1.7672
H26	5.2420	4.2248	6.6305	2.8026	7.7523	2.1701	9.1087	1.0942	5.1251	5.4195	4.4130	4.7517	6.9785	6.7524	3.1218	2.5770	7.6715	7.8710	2.5167	3.0717	9.9192	9.3983	9.2307	1.7685	1.7672

picture of Octane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	113.318	C1	C2	H11	109.276
C1	C2	H12	109.276	C1	C3	C5	113.357
C1	C3	H13	109.326	C1	C3	H14	109.326
C2	C1	C3	113.318	C2	C1	H9	109.276
C2	C1	H10	109.276	C2	C4	C6	113.357
C2	C4	H15	109.326	C2	C4	H16	109.326
C3	C1	H9	109.272	C3	C1	H10	109.272
C3	C5	C7	113.055	C3	C5	H17	109.317
C3	C5	H18	109.317	C4	C2	H11	109.272
C4	C2	H12	109.272	C4	C6	C8	113.055
C4	C6	H19	109.317	C4	C6	H20	109.317
C5	C3	H13	109.208	C5	C3	H14	109.208
C5	C7	H21	111.299	C5	C7	H22	111.165
C5	C7	H23	111.165	C6	C4	H15	109.208
C6	C4	H16	109.208	C6	C8	H24	111.299
C6	C8	H25	111.165	C6	C8	H26	111.165
C7	C5	H17	109.348	C7	C5	H18	109.348
C8	C6	H19	109.348	C8	C6	H20	109.348
H9	C1	H10	106.178	H11	C2	H12	106.178
H13	C3	H14	106.165	H15	C4	H16	106.165
H17	C5	H18	106.226	H19	C6	H20	106.226
H21	C7	H22	107.705	H21	C7	H23	107.705
H22	C7	H23	107.625	H24	C8	H25	107.705
H24	C8	H26	107.705	H25	C8	H26	107.625

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for C₈H₁₈ (Octane)

using model chemistry: G2

States and conformations

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All results from a given calculation for C8H18 (Octane)

using model chemistry: G2

States and conformations

All results from a given calculation for C₈H₁₈ (Octane)