CCCBDB calculation results Page

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

Energy calculated at CBS-Q

	hartrees
Energy at 0K	-314.986012
Energy at 298.15K	-315.006646
Nuclear repulsion energy	374.475502

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 CBS-Q

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3249	3249	0.00
2	A_g	3182	3182	0.00
3	A_g	3176	3176	0.00
4	A_g	3169	3169	0.00
5	A_g	3163	3163	0.00
6	A_g	1646	1646	0.00
7	A_g	1634	1634	0.00
8	A_g	1626	1626	0.00
9	A_g	1623	1623	0.00
10	A_g	1564	1564	0.00
11	A_g	1554	1554	0.00
12	A_g	1519	1519	0.00
13	A_g	1416	1416	0.00
14	A_g	1248	1248	0.00
15	A_g	1138	1138	0.00
16	A_g	1121	1121	0.00
17	A_g	1079	1079	0.00
18	A_g	967	967	0.00
19	A_g	503	503	0.00
20	A_g	290	290	0.00
21	A_g	209	209	0.00
22	A_u	3249	3249	257.64
23	A_u	3229	3229	111.53
24	A_u	3204	3204	1.74
25	A_u	3185	3185	0.08
26	A_u	1635	1635	10.05
27	A_u	1457	1457	0.46
28	A_u	1432	1432	0.55
29	A_u	1343	1343	0.01
30	A_u	1116	1116	0.11
31	A_u	946	946	0.44
32	A_u	805	805	0.78
33	A_u	775	775	3.26
34	A_u	263	263	0.00
35	A_u	172	172	0.00
36	A_u	73	73	0.00
37	A_u	52	52	0.01
38	B_g	3248	3248	0.00
39	B_g	3216	3216	0.00
40	B_g	3192	3192	0.00
41	B_g	3183	3183	0.00
42	B_g	1635	1635	0.00
43	B_g	1457	1457	0.00
44	B_g	1443	1443	0.00
45	B_g	1391	1391	0.00
46	B_g	1312	1312	0.00
47	B_g	1036	1036	0.00
48	B_g	863	863	0.00
49	B_g	780	780	0.00
50	B_g	266	266	0.00
51	B_g	147	147	0.00
52	B_g	119	119	0.00
53	B_u	3249	3249	125.65
54	B_u	3182	3182	42.33
55	B_u	3180	3180	259.25
56	B_u	3170	3170	8.09
57	B_u	3163	3163	1.71
58	B_u	1650	1650	4.96
59	B_u	1641	1641	0.88
60	B_u	1627	1627	0.62
61	B_u	1623	1623	0.29
62	B_u	1558	1558	3.26
63	B_u	1547	1547	0.48
64	B_u	1472	1472	2.44
65	B_u	1355	1355	5.26
66	B_u	1186	1186	2.66
67	B_u	1136	1136	0.21
68	B_u	1079	1079	0.31
69	B_u	953	953	2.13
70	B_u	499	499	0.15
71	B_u	361	361	0.02
72	B_u	84	84	0.00

Unscaled Zero Point Vibrational Energy (zpe) 57508.3 cm^-1
Scaled (by 1) Zero Point Vibrational Energy (zpe) 57508.3 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 CBS-Q

A	B	C
0.35511	0.01630	0.01596

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

Geometric Data calculated at CBS-Q

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.766	0.000
C2	-0.000	-0.766	0.000
C3	-1.405	1.374	0.000
C4	1.405	-1.374	0.000
C5	-1.405	2.905	0.000
C6	1.405	-2.905	0.000
C7	-2.812	3.505	0.000
C8	2.812	-3.505	0.000
H9	0.549	1.126	0.872
H10	0.549	1.126	-0.872
H11	-0.549	-1.126	0.872
H12	-0.549	-1.126	-0.872
H13	-1.954	1.014	-0.872
H14	-1.954	1.014	0.872
H15	1.954	-1.014	-0.872
H16	1.954	-1.014	0.872
H17	-0.858	3.266	0.872
H18	-0.858	3.266	-0.872
H19	0.858	-3.266	0.872
H20	0.858	-3.266	-0.872
H21	-2.778	4.593	0.000
H22	-3.374	3.192	-0.879
H23	-3.374	3.192	0.879
H24	2.778	-4.593	0.000
H25	3.374	-3.192	-0.879
H26	3.374	-3.192	0.879

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		1.5313	1.5311	2.5590	2.5595	3.9300	3.9261	5.1131	1.0913	1.0913	2.1540	2.1540	2.1546	2.1546	2.7830	2.7830	2.7836	2.7836	4.2130	4.2130	4.7296	4.2478	4.2478	6.0358	5.2737	5.2737
C2	1.5313		2.5590	1.5311	3.9300	2.5595	5.1131	3.9261	2.1540	2.1540	1.0913	1.0913	2.7830	2.7830	2.1546	2.1546	4.2130	4.2130	2.7836	2.7836	6.0358	5.2737	5.2737	4.7296	4.2478	4.2478
C3	1.5311	2.5590		3.9296	1.5313	5.1186	2.5540	6.4485	2.1538	2.1538	2.7821	2.7821	1.0915	1.0915	4.2124	4.2124	2.1540	2.1540	5.2351	5.2351	3.5001	2.8203	2.8203	7.2868	6.6670	6.6670
C4	2.5590	1.5311	3.9296		5.1186	1.5313	6.4485	2.5540	2.7821	2.7821	2.1538	2.1538	4.2124	4.2124	1.0915	1.0915	5.2351	5.2351	2.1540	2.1540	7.2868	6.6670	6.6670	3.5001	2.8203	2.8203
C5	2.5595	3.9300	1.5313	5.1186		6.4535	1.5297	7.6726	2.7826	2.7826	4.2118	4.2118	2.1532	2.1532	5.2348	5.2348	1.0906	1.0906	6.6302	6.6302	2.1762	2.1752	2.1752	8.5858	7.7959	7.7959
C6	3.9300	2.5595	5.1186	1.5313	6.4535		7.6726	1.5297	4.2118	4.2118	2.7826	2.7826	5.2348	5.2348	2.1532	2.1532	6.6302	6.6302	1.0906	1.0906	8.5858	7.7959	7.7959	2.1762	2.1752	2.1752
C7	3.9261	5.1131	2.5540	6.4485	1.5297	7.6726		8.9872	4.2091	4.2091	5.2275	5.2275	2.7750	2.7750	6.6257	6.6257	2.1528	2.1528	7.7508	7.7508	1.0885	1.0891	1.0891	9.8401	9.1587	9.1587
C8	5.1131	3.9261	6.4485	2.5540	7.6726	1.5297	8.9872		5.2275	5.2275	4.2091	4.2091	6.6257	6.6257	2.7750	2.7750	7.7508	7.7508	2.1528	2.1528	9.8401	9.1587	9.1587	1.0885	1.0891	1.0891
H9	1.0913	2.1540	2.1538	2.7821	2.7826	4.2118	4.2091	5.2275		1.7441	2.5049	3.0523	3.0527	2.5054	3.0978	2.5602	2.5612	3.0986	4.4025	4.7354	4.8838	4.7666	4.4335	6.1996	5.4485	5.1595
H10	1.0913	2.1540	2.1538	2.7821	2.7826	4.2118	4.2091	5.2275	1.7441		3.0523	2.5049	2.5054	3.0527	2.5602	3.0978	3.0986	2.5612	4.7354	4.4025	4.8838	4.4335	4.7666	6.1996	5.1595	5.4485
H11	2.1540	1.0913	2.7821	2.1538	4.2118	2.7826	5.2275	4.2091	2.5049	3.0523		1.7441	3.0978	2.5602	3.0527	2.5054	4.4025	4.7354	2.5612	3.0986	6.1996	5.4485	5.1595	4.8838	4.7666	4.4335
H12	2.1540	1.0913	2.7821	2.1538	4.2118	2.7826	5.2275	4.2091	3.0523	2.5049	1.7441		2.5602	3.0978	2.5054	3.0527	4.7354	4.4025	3.0986	2.5612	6.1996	5.1595	5.4485	4.8838	4.4335	4.7666
H13	2.1546	2.7830	1.0915	4.2124	2.1532	5.2348	2.7750	6.6257	3.0527	2.5054	3.0978	2.5602		1.7442	4.4032	4.7361	3.0516	2.5041	5.4102	5.1214	3.7745	2.5993	3.1340	7.3889	6.7879	7.0101
H14	2.1546	2.7830	1.0915	4.2124	2.1532	5.2348	2.7750	6.6257	2.5054	3.0527	2.5602	3.0978	1.7442		4.7361	4.4032	2.5041	3.0516	5.1214	5.4102	3.7745	3.1340	2.5993	7.3889	7.0101	6.7879
H15	2.7830	2.1546	4.2124	1.0915	5.2348	2.1532	6.6257	2.7750	3.0978	2.5602	3.0527	2.5054	4.4032	4.7361		1.7442	5.4102	5.1214	3.0516	2.5041	7.3889	6.7879	7.0101	3.7745	2.5993	3.1340
H16	2.7830	2.1546	4.2124	1.0915	5.2348	2.1532	6.6257	2.7750	2.5602	3.0978	2.5054	3.0527	4.7361	4.4032	1.7442		5.1214	5.4102	2.5041	3.0516	7.3889	7.0101	6.7879	3.7745	3.1340	2.5993
H17	2.7836	4.2130	2.1540	5.2351	1.0906	6.6302	2.1528	7.7508	2.5612	3.0986	4.4025	4.7354	3.0516	2.5041	5.4102	5.1214		1.7437	6.7535	6.9750	2.4915	3.0658	2.5168	8.7032	7.9167	7.7207
H18	2.7836	4.2130	2.1540	5.2351	1.0906	6.6302	2.1528	7.7508	3.0986	2.5612	4.7354	4.4025	2.5041	3.0516	5.1214	5.4102	1.7437		6.9750	6.7535	2.4915	2.5168	3.0658	8.7032	7.7207	7.9167
H19	4.2130	2.7836	5.2351	2.1540	6.6302	1.0906	7.7508	2.1528	4.4025	4.7354	2.5612	3.0986	5.4102	5.1214	3.0516	2.5041	6.7535	6.9750		1.7437	8.7032	7.9167	7.7207	2.4915	3.0658	2.5168
H20	4.2130	2.7836	5.2351	2.1540	6.6302	1.0906	7.7508	2.1528	4.7354	4.4025	3.0986	2.5612	5.1214	5.4102	2.5041	3.0516	6.9750	6.7535	1.7437		8.7032	7.7207	7.9167	2.4915	2.5168	3.0658
H21	4.7296	6.0358	3.5001	7.2868	2.1762	8.5858	1.0885	9.8401	4.8838	4.8838	6.1996	6.1996	3.7745	3.7745	7.3889	7.3889	2.4915	2.4915	8.7032	8.7032		1.7582	1.7582	10.7357	9.9609	9.9609
H22	4.2478	5.2737	2.8203	6.6670	2.1752	7.7959	1.0891	9.1587	4.7666	4.4335	5.4485	5.1595	2.5993	3.1340	6.7879	7.0101	3.0658	2.5168	7.9167	7.7207	1.7582		1.7575	9.9609	9.2886	9.4534
H23	4.2478	5.2737	2.8203	6.6670	2.1752	7.7959	1.0891	9.1587	4.4335	4.7666	5.1595	5.4485	3.1340	2.5993	7.0101	6.7879	2.5168	3.0658	7.7207	7.9167	1.7582	1.7575		9.9609	9.4534	9.2886
H24	6.0358	4.7296	7.2868	3.5001	8.5858	2.1762	9.8401	1.0885	6.1996	6.1996	4.8838	4.8838	7.3889	7.3889	3.7745	3.7745	8.7032	8.7032	2.4915	2.4915	10.7357	9.9609	9.9609		1.7582	1.7582
H25	5.2737	4.2478	6.6670	2.8203	7.7959	2.1752	9.1587	1.0891	5.4485	5.1595	4.7666	4.4335	6.7879	7.0101	2.5993	3.1340	7.9167	7.7207	3.0658	2.5168	9.9609	9.2886	9.4534	1.7582		1.7575
H26	5.2737	4.2478	6.6670	2.8203	7.7959	2.1752	9.1587	1.0891	5.1595	5.4485	4.4335	4.7666	7.0101	6.7879	3.1340	2.5993	7.7207	7.9167	2.5168	3.0658	9.9609	9.4534	9.2886	1.7582	1.7575

picture of Octane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	113.362	C1	C2	H11	109.286
C1	C2	H12	109.286	C1	C3	C5	113.397
C1	C3	H13	109.336	C1	C3	H14	109.336
C2	C1	C3	113.362	C2	C1	H9	109.286
C2	C1	H10	109.286	C2	C4	C6	113.397
C2	C4	H15	109.336	C2	C4	H16	109.336
C3	C1	H9	109.281	C3	C1	H10	109.281
C3	C5	C7	113.102	C3	C5	H17	109.329
C3	C5	H18	109.329	C4	C2	H11	109.281
C4	C2	H12	109.281	C4	C6	C8	113.102
C4	C6	H19	109.329	C4	C6	H20	109.329
C5	C3	H13	109.219	C5	C3	H14	109.219
C5	C7	H21	111.319	C5	C7	H22	111.202
C5	C7	H23	111.202	C6	C4	H15	109.219
C6	C4	H16	109.219	C6	C8	H24	111.319
C6	C8	H25	111.202	C6	C8	H26	111.202
C7	C5	H17	109.345	C7	C5	H18	109.345
C8	C6	H19	109.345	C8	C6	H20	109.345
H9	C1	H10	106.088	H11	C2	H12	106.088
H13	C3	H14	106.074	H15	C4	H16	106.074
H17	C5	H18	106.155	H19	C6	H20	106.155
H21	C7	H22	107.682	H21	C7	H23	107.682
H22	C7	H23	107.572	H24	C8	H25	107.682
H24	C8	H26	107.682	H25	C8	H26	107.572

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for C₈H₁₈ (Octane)

using model chemistry: CBS-Q

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All results from a given calculation for C8H18 (Octane)

using model chemistry: CBS-Q

States and conformations

All results from a given calculation for C₈H₁₈ (Octane)