CCCBDB calculation results Page

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

Energy calculated at MP2/TZVP

	hartrees
Energy at 0K	-314.758892
Energy at 298.15K	-314.778299
HF Energy	-313.537588
Nuclear repulsion energy	375.759596

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 MP2/TZVP

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3166	3001	0.00
2	A_g	3076	2916	0.00
3	A_g	3074	2914	0.00
4	A_g	3059	2900	0.00
5	A_g	3055	2896	0.00
6	A_g	1531	1451	0.00
7	A_g	1518	1439	0.00
8	A_g	1510	1431	0.00
9	A_g	1505	1427	0.00
10	A_g	1436	1361	0.00
11	A_g	1428	1353	0.00
12	A_g	1405	1332	0.00
13	A_g	1311	1243	0.00
14	A_g	1183	1121	0.00
15	A_g	1106	1049	0.00
16	A_g	1085	1028	0.00
17	A_g	1032	979	0.00
18	A_g	926	878	0.00
19	A_g	474	450	0.00
20	A_g	280	265	0.00
21	A_g	194	184	0.00
22	A_u	3164	2999	106.64
23	A_u	3134	2971	118.95
24	A_u	3118	2956	0.01
25	A_u	3098	2936	0.34
26	A_u	1523	1444	13.97
27	A_u	1347	1277	0.69
28	A_u	1332	1263	0.72
29	A_u	1255	1190	0.02
30	A_u	1045	990	0.10
31	A_u	898	851	0.37
32	A_u	774	734	0.59
33	A_u	733	694	2.99
34	A_u	245	232	0.00
35	A_u	153	145	0.00
36	A_u	57	54	0.00
37	A_u	44	41	0.01
38	B_g	3164	2999	0.00
39	B_g	3128	2965	0.00
40	B_g	3107	2945	0.00
41	B_g	3093	2932	0.00
42	B_g	1523	1444	0.00
43	B_g	1351	1280	0.00
44	B_g	1334	1265	0.00
45	B_g	1297	1229	0.00
46	B_g	1229	1165	0.00
47	B_g	977	926	0.00
48	B_g	825	782	0.00
49	B_g	750	711	0.00
50	B_g	247	235	0.00
51	B_g	127	121	0.00
52	B_g	104	98	0.00
53	B_u	3166	3001	70.01
54	B_u	3076	2916	149.46
55	B_u	3075	2914	55.14
56	B_u	3066	2906	31.01
57	B_u	3055	2896	1.63
58	B_u	1533	1453	13.30
59	B_u	1525	1445	1.10
60	B_u	1512	1434	0.39
61	B_u	1505	1427	0.01
62	B_u	1434	1360	4.99
63	B_u	1426	1352	1.35
64	B_u	1365	1294	1.38
65	B_u	1252	1187	1.75
66	B_u	1121	1063	3.25
67	B_u	1099	1042	0.33
68	B_u	1044	990	0.52
69	B_u	910	863	2.28
70	B_u	475	451	0.11
71	B_u	339	321	0.00
72	B_u	77	73	0.00

Unscaled Zero Point Vibrational Energy (zpe) 54792.1 cm^-1
Scaled (by 0.9479) Zero Point Vibrational Energy (zpe) 51937.4 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 MP2/TZVP

A	B	C
0.35975	0.01645	0.01611

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

Geometric Data calculated at MP2/TZVP

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.001	0.762	0.000
C2	-0.001	-0.762	0.000
C3	-1.398	1.367	0.000
C4	1.398	-1.367	0.000
C5	-1.398	2.891	0.000
C6	1.398	-2.891	0.000
C7	-2.803	3.480	0.000
C8	2.803	-3.480	0.000
H9	0.548	1.120	0.878
H10	0.548	1.120	-0.878
H11	-0.548	-1.120	0.878
H12	-0.548	-1.120	-0.878
H13	-1.944	1.007	-0.878
H14	-1.944	1.007	0.878
H15	1.944	-1.007	-0.878
H16	1.944	-1.007	0.878
H17	-0.849	3.246	0.877
H18	-0.849	3.246	-0.877
H19	0.849	-3.246	0.877
H20	0.849	-3.246	-0.877
H21	-2.781	4.571	0.000
H22	-3.358	3.155	-0.882
H23	-3.358	3.155	0.882
H24	2.781	-4.571	0.000
H25	3.358	-3.155	-0.882
H26	3.358	-3.155	0.882

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		1.5238	1.5236	2.5463	2.5473	3.9110	3.9054	5.0843	1.0952	1.0952	2.1483	2.1483	2.1481	2.1481	2.7711	2.7711	2.7686	2.7686	4.1900	4.1900	4.7167	4.2175	4.2175	6.0141	5.2339	5.2339
C2	1.5238		2.5463	1.5236	3.9110	2.5473	5.0843	3.9054	2.1483	2.1483	1.0952	1.0952	2.7711	2.7711	2.1481	2.1481	4.1900	4.1900	2.7686	2.7686	6.0141	5.2339	5.2339	4.7167	4.2175	4.2175
C3	1.5236	2.5463		3.9101	1.5240	5.0936	2.5380	6.4144	2.1488	2.1488	2.7714	2.7714	1.0953	1.0953	4.1925	4.1925	2.1452	2.1452	5.2060	5.2060	3.4898	2.7962	2.7962	7.2610	6.6216	6.6216
C4	2.5463	1.5236	3.9101		5.0936	1.5240	6.4144	2.5380	2.7714	2.7714	2.1488	2.1488	4.1925	4.1925	1.0953	1.0953	5.2060	5.2060	2.1452	2.1452	7.2610	6.6216	6.6216	3.4898	2.7962	2.7962
C5	2.5473	3.9110	1.5240	5.0936		6.4223	1.5242	7.6316	2.7735	2.7735	4.1934	4.1934	2.1491	2.1491	5.2093	5.2093	1.0939	1.0939	6.5944	6.5944	2.1763	2.1659	2.1659	8.5524	7.7428	7.7428
C6	3.9110	2.5473	5.0936	1.5240	6.4223		7.6316	1.5242	4.1934	4.1934	2.7735	2.7735	5.2093	5.2093	2.1491	2.1491	6.5944	6.5944	1.0939	1.0939	8.5524	7.7428	7.7428	2.1763	2.1659	2.1659
C7	3.9054	5.0843	2.5380	6.4144	1.5242	7.6316		8.9377	4.1918	4.1918	5.1984	5.1984	2.7613	2.7613	6.5916	6.5916	2.1546	2.1546	7.7045	7.7045	1.0908	1.0916	1.0916	9.7984	9.0978	9.0978
C8	5.0843	3.9054	6.4144	2.5380	7.6316	1.5242	8.9377		5.1984	5.1984	4.1918	4.1918	6.5916	6.5916	2.7613	2.7613	7.7045	7.7045	2.1546	2.1546	9.7984	9.0978	9.0978	1.0908	1.0916	1.0916
H9	1.0952	2.1483	2.1488	2.7714	2.7735	4.1934	4.1918	5.1984		1.7569	2.4941	3.0507	3.0511	2.4945	3.0924	2.5449	2.5441	3.0912	4.3770	4.7161	4.8745	4.7430	4.4042	6.1765	5.4107	5.1163
H10	1.0952	2.1483	2.1488	2.7714	2.7735	4.1934	4.1918	5.1984	1.7569		3.0507	2.4941	2.4945	3.0511	2.5449	3.0924	3.0912	2.5441	4.7161	4.3770	4.8745	4.4042	4.7430	6.1765	5.1163	5.4107
H11	2.1483	1.0952	2.7714	2.1488	4.1934	2.7735	5.1984	4.1918	2.4941	3.0507		1.7569	3.0924	2.5449	3.0511	2.4945	4.3770	4.7161	2.5441	3.0912	6.1765	5.4107	5.1163	4.8745	4.7430	4.4042
H12	2.1483	1.0952	2.7714	2.1488	4.1934	2.7735	5.1984	4.1918	3.0507	2.4941	1.7569		2.5449	3.0924	2.4945	3.0511	4.7161	4.3770	3.0912	2.5441	6.1765	5.1163	5.4107	4.8745	4.4042	4.7430
H13	2.1481	2.7711	1.0953	4.1925	2.1491	5.2093	2.7613	6.5916	3.0511	2.4945	3.0924	2.5449		1.7567	4.3793	4.7185	3.0486	2.4922	5.3834	5.0890	3.7644	2.5714	3.1162	7.3633	6.7410	6.9671
H14	2.1481	2.7711	1.0953	4.1925	2.1491	5.2093	2.7613	6.5916	2.4945	3.0511	2.5449	3.0924	1.7567		4.7185	4.3793	2.4922	3.0486	5.0890	5.3834	3.7644	3.1162	2.5714	7.3633	6.9671	6.7410
H15	2.7711	2.1481	4.1925	1.0953	5.2093	2.1491	6.5916	2.7613	3.0924	2.5449	3.0511	2.4945	4.3793	4.7185		1.7567	5.3834	5.0890	3.0486	2.4922	7.3633	6.7410	6.9671	3.7644	2.5714	3.1162
H16	2.7711	2.1481	4.1925	1.0953	5.2093	2.1491	6.5916	2.7613	2.5449	3.0924	2.4945	3.0511	4.7185	4.3793	1.7567		5.0890	5.3834	2.4922	3.0486	7.3633	6.9671	6.7410	3.7644	3.1162	2.5714
H17	2.7686	4.1900	2.1452	5.2060	1.0939	6.5944	2.1546	7.7045	2.5441	3.0912	4.3770	4.7161	3.0486	2.4922	5.3834	5.0890		1.7550	6.7112	6.9369	2.5013	3.0656	2.5103	8.6637	7.8599	7.6604
H18	2.7686	4.1900	2.1452	5.2060	1.0939	6.5944	2.1546	7.7045	3.0912	2.5441	4.7161	4.3770	2.4922	3.0486	5.0890	5.3834	1.7550		6.9369	6.7112	2.5013	2.5103	3.0656	8.6637	7.6604	7.8599
H19	4.1900	2.7686	5.2060	2.1452	6.5944	1.0939	7.7045	2.1546	4.3770	4.7161	2.5441	3.0912	5.3834	5.0890	3.0486	2.4922	6.7112	6.9369		1.7550	8.6637	7.8599	7.6604	2.5013	3.0656	2.5103
H20	4.1900	2.7686	5.2060	2.1452	6.5944	1.0939	7.7045	2.1546	4.7161	4.3770	3.0912	2.5441	5.0890	5.3834	2.4922	3.0486	6.9369	6.7112	1.7550		8.6637	7.6604	7.8599	2.5013	2.5103	3.0656
H21	4.7167	6.0141	3.4898	7.2610	2.1763	8.5524	1.0908	9.7984	4.8745	4.8745	6.1765	6.1765	3.7644	3.7644	7.3633	7.3633	2.5013	2.5013	8.6637	8.6637		1.7649	1.7649	10.7011	9.9076	9.9076
H22	4.2175	5.2339	2.7962	6.6216	2.1659	7.7428	1.0916	9.0978	4.7430	4.4042	5.4107	5.1163	2.5714	3.1162	6.7410	6.9671	3.0656	2.5103	7.8599	7.6604	1.7649		1.7641	9.9076	9.2156	9.3829
H23	4.2175	5.2339	2.7962	6.6216	2.1659	7.7428	1.0916	9.0978	4.4042	4.7430	5.1163	5.4107	3.1162	2.5714	6.9671	6.7410	2.5103	3.0656	7.6604	7.8599	1.7649	1.7641		9.9076	9.3829	9.2156
H24	6.0141	4.7167	7.2610	3.4898	8.5524	2.1763	9.7984	1.0908	6.1765	6.1765	4.8745	4.8745	7.3633	7.3633	3.7644	3.7644	8.6637	8.6637	2.5013	2.5013	10.7011	9.9076	9.9076		1.7649	1.7649
H25	5.2339	4.2175	6.6216	2.7962	7.7428	2.1659	9.0978	1.0916	5.4107	5.1163	4.7430	4.4042	6.7410	6.9671	2.5714	3.1162	7.8599	7.6604	3.0656	2.5103	9.9076	9.2156	9.3829	1.7649		1.7641
H26	5.2339	4.2175	6.6216	2.7962	7.7428	2.1659	9.0978	1.0916	5.1163	5.4107	4.4042	4.7430	6.9671	6.7410	3.1162	2.5714	7.6604	7.8599	2.5103	3.0656	9.9076	9.3829	9.2156	1.7649	1.7641

picture of Octane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	113.350	C1	C2	H11	109.128
C1	C2	H12	109.128	C1	C3	C5	113.405
C1	C3	H13	109.121	C1	C3	H14	109.121
C2	C1	C3	113.350	C2	C1	H9	109.128
C2	C1	H10	109.128	C2	C4	C6	113.405
C2	C4	H15	109.121	C2	C4	H16	109.121
C3	C1	H9	109.178	C3	C1	H10	109.178
C3	C5	C7	112.742	C3	C5	H17	108.949
C3	C5	H18	108.949	C4	C2	H11	109.178
C4	C2	H12	109.178	C4	C6	C8	112.742
C4	C6	H19	108.949	C4	C6	H20	108.949
C5	C3	H13	109.171	C5	C3	H14	109.171
C5	C7	H21	111.583	C5	C7	H22	110.708
C5	C7	H23	110.708	C6	C4	H15	109.171
C6	C4	H16	109.171	C6	C8	H24	111.583
C6	C8	H25	110.708	C6	C8	H26	110.708
C7	C5	H17	109.671	C7	C5	H18	109.671
C8	C6	H19	109.671	C8	C6	H20	109.671
H9	C1	H10	106.662	H11	C2	H12	106.662
H13	C3	H14	106.630	H15	C4	H16	106.630
H17	C5	H18	106.672	H19	C6	H20	106.672
H21	C7	H22	107.941	H21	C7	H23	107.941
H22	C7	H23	107.817	H24	C8	H25	107.941
H24	C8	H26	107.941	H25	C8	H26	107.817

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for C₈H₁₈ (Octane)

using model chemistry: MP2/TZVP

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: MP2/TZVP

States and conformations

All results from a given calculation for C₈H₁₈ (Octane)