CCCBDB calculation results Page

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

Energy calculated at PBEPBE/6-31G(2df,p)

	hartrees
Energy at 0K	-315.262842
Energy at 298.15K	-315.281964
Nuclear repulsion energy	372.683773

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 PBEPBE/6-31G(2df,p)

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3050	3019	0.00
2	A_g	2969	2939	0.00
3	A_g	2955	2924	0.00
4	A_g	2940	2910	0.00
5	A_g	2937	2907	0.00
6	A_g	1461	1446	0.00
7	A_g	1447	1432	0.00
8	A_g	1434	1419	0.00
9	A_g	1430	1416	0.00
10	A_g	1358	1345	0.00
11	A_g	1349	1335	0.00
12	A_g	1336	1322	0.00
13	A_g	1254	1241	0.00
14	A_g	1124	1113	0.00
15	A_g	1065	1054	0.00
16	A_g	1046	1035	0.00
17	A_g	987	977	0.00
18	A_g	887	878	0.00
19	A_g	452	447	0.00
20	A_g	269	266	0.00
21	A_g	186	184	0.00
22	A_u	3043	3012	93.22
23	A_u	3006	2975	128.62
24	A_u	2988	2958	0.57
25	A_u	2966	2935	0.20
26	A_u	1448	1433	11.24
27	A_u	1295	1282	0.51
28	A_u	1275	1262	0.24
29	A_u	1194	1182	0.03
30	A_u	1005	994	0.31
31	A_u	849	841	0.96
32	A_u	731	724	1.45
33	A_u	712	705	7.31
34	A_u	238	236	0.00
35	A_u	161	159	0.00
36	A_u	74	73	0.00
37	A_u	46	45	0.01
38	B_g	3043	3012	0.00
39	B_g	2999	2968	0.00
40	B_g	2976	2946	0.00
41	B_g	2961	2931	0.00
42	B_g	1448	1433	0.00
43	B_g	1295	1282	0.00
44	B_g	1285	1272	0.00
45	B_g	1238	1226	0.00
46	B_g	1166	1154	0.00
47	B_g	931	921	0.00
48	B_g	778	770	0.00
49	B_g	714	707	0.00
50	B_g	241	239	0.00
51	B_g	138	137	0.00
52	B_g	108	107	0.00
53	B_u	3050	3019	66.92
54	B_u	2969	2939	79.56
55	B_u	2957	2926	144.77
56	B_u	2948	2917	12.74
57	B_u	2936	2906	1.61
58	B_u	1465	1450	5.75
59	B_u	1455	1440	1.10
60	B_u	1439	1424	0.63
61	B_u	1430	1415	0.20
62	B_u	1357	1343	1.20
63	B_u	1351	1337	2.81
64	B_u	1300	1287	3.16
65	B_u	1204	1192	6.67
66	B_u	1072	1061	3.41
67	B_u	1056	1045	0.74
68	B_u	1007	997	0.39
69	B_u	869	860	3.60
70	B_u	456	451	0.13
71	B_u	322	319	0.06
72	B_u	78	77	0.01

Unscaled Zero Point Vibrational Energy (zpe) 52506.0 cm^-1
Scaled (by 0.9897) Zero Point Vibrational Energy (zpe) 51965.1 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 PBEPBE/6-31G(2df,p)

A	B	C
0.35468	0.01619	0.01585

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

Geometric Data calculated at PBEPBE/6-31G(2df,p)

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.002	0.767	0.000
C2	-0.002	-0.767	0.000
C3	-1.402	1.383	0.000
C4	1.402	-1.383	0.000
C5	-1.402	2.917	0.000
C6	1.402	-2.917	0.000
C7	-2.810	3.520	0.000
C8	2.810	-3.520	0.000
H9	0.563	1.131	0.883
H10	0.563	1.131	-0.883
H11	-0.563	-1.131	0.883
H12	-0.563	-1.131	-0.883
H13	-1.962	1.018	-0.882
H14	-1.962	1.018	0.882
H15	1.962	-1.018	-0.882
H16	1.962	-1.018	0.882
H17	-0.842	3.280	0.882
H18	-0.842	3.280	-0.882
H19	0.842	-3.280	0.882
H20	0.842	-3.280	-0.882
H21	-2.780	4.622	0.000
H22	-3.380	3.202	-0.889
H23	-3.380	3.202	0.889
H24	2.780	-4.622	0.000
H25	3.380	-3.202	-0.889
H26	3.380	-3.202	0.889

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		1.5336	1.5334	2.5650	2.5679	3.9404	3.9357	5.1245	1.1073	1.1073	2.1684	2.1684	2.1685	2.1685	2.7937	2.7937	2.7938	2.7938	4.2258	4.2258	4.7544	4.2618	4.2618	6.0625	5.2867	5.2867
C2	1.5336		2.5650	1.5334	3.9404	2.5679	5.1245	3.9357	2.1684	2.1684	1.1073	1.1073	2.7937	2.7937	2.1685	2.1685	4.2258	4.2258	2.7938	2.7938	6.0625	5.2867	5.2867	4.7544	4.2618	4.2618
C3	1.5334	2.5650		3.9382	1.5339	5.1329	2.5595	6.4636	2.1684	2.1684	2.7937	2.7937	1.1074	1.1074	4.2260	4.2260	2.1658	2.1658	5.2489	5.2489	3.5202	2.8308	2.8308	7.3175	6.6841	6.6841
C4	2.5650	1.5334	3.9382		5.1329	1.5339	6.4636	2.5595	2.7937	2.7937	2.1684	2.1684	4.2260	4.2260	1.1074	1.1074	5.2489	5.2489	2.1658	2.1658	7.3175	6.6841	6.6841	3.5202	2.8308	2.8308
C5	2.5679	3.9404	1.5339	5.1329		6.4722	1.5317	7.6924	2.7975	2.7975	4.2274	4.2274	2.1678	2.1678	5.2513	5.2513	1.1063	1.1063	6.6489	6.6489	2.1925	2.1878	2.1878	8.6209	7.8163	7.8163
C6	3.9404	2.5679	5.1329	1.5339	6.4722		7.6924	1.5317	4.2274	4.2274	2.7975	2.7975	5.2513	5.2513	2.1678	2.1678	6.6489	6.6489	1.1063	1.1063	8.6209	7.8163	7.8163	2.1925	2.1878	2.1878
C7	3.9357	5.1245	2.5595	6.4636	1.5317	7.6924		9.0083	4.2261	4.2261	5.2409	5.2409	2.7857	2.7857	6.6442	6.6442	2.1701	2.1701	7.7687	7.7687	1.1020	1.1034	1.1034	9.8764	9.1811	9.1811
C8	5.1245	3.9357	6.4636	2.5595	7.6924	1.5317	9.0083		5.2409	5.2409	4.2261	4.2261	6.6442	6.6442	2.7857	2.7857	7.7687	7.7687	2.1701	2.1701	9.8764	9.1811	9.1811	1.1020	1.1034	1.1034
H9	1.1073	2.1684	2.1684	2.7937	2.7975	4.2274	4.2261	5.2409		1.7654	2.5274	3.0829	3.0831	2.5279	3.1134	2.5647	2.5666	3.1148	4.4201	4.7594	4.9129	4.7931	4.4537	6.2288	5.4638	5.1687
H10	1.1073	2.1684	2.1684	2.7937	2.7975	4.2274	4.2261	5.2409	1.7654		3.0829	2.5274	2.5279	3.0831	2.5647	3.1134	3.1148	2.5666	4.7594	4.4201	4.9129	4.4537	4.7931	6.2288	5.1687	5.4638
H11	2.1684	1.1073	2.7937	2.1684	4.2274	2.7975	5.2409	4.2261	2.5274	3.0829		1.7654	3.1134	2.5647	3.0831	2.5279	4.4201	4.7594	2.5666	3.1148	6.2288	5.4638	5.1687	4.9129	4.7931	4.4537
H12	2.1684	1.1073	2.7937	2.1684	4.2274	2.7975	5.2409	4.2261	3.0829	2.5274	1.7654		2.5647	3.1134	2.5279	3.0831	4.7594	4.4201	3.1148	2.5666	6.2288	5.1687	5.4638	4.9129	4.4537	4.7931
H13	2.1685	2.7937	1.1074	4.2260	2.1678	5.2513	2.7857	6.6442	3.0831	2.5279	3.1134	2.5647		1.7649	4.4213	4.7605	3.0802	2.5247	5.4263	5.1314	3.7998	2.6040	3.1492	7.4212	6.8081	7.0347
H14	2.1685	2.7937	1.1074	4.2260	2.1678	5.2513	2.7857	6.6442	2.5279	3.0831	2.5647	3.1134	1.7649		4.7605	4.4213	2.5247	3.0802	5.1314	5.4263	3.7998	3.1492	2.6040	7.4212	7.0347	6.8081
H15	2.7937	2.1685	4.2260	1.1074	5.2513	2.1678	6.6442	2.7857	3.1134	2.5647	3.0831	2.5279	4.4213	4.7605		1.7649	5.4263	5.1314	3.0802	2.5247	7.4212	6.8081	7.0347	3.7998	2.6040	3.1492
H16	2.7937	2.1685	4.2260	1.1074	5.2513	2.1678	6.6442	2.7857	2.5647	3.1134	2.5279	3.0831	4.7605	4.4213	1.7649		5.1314	5.4263	2.5247	3.0802	7.4212	7.0347	6.8081	3.7998	3.1492	2.6040
H17	2.7938	4.2258	2.1658	5.2489	1.1063	6.6489	2.1701	7.7687	2.5666	3.1148	4.4201	4.7594	3.0802	2.5247	5.4263	5.1314		1.7642	6.7721	6.9981	2.5173	3.0965	2.5402	8.7368	7.9354	7.7353
H18	2.7938	4.2258	2.1658	5.2489	1.1063	6.6489	2.1701	7.7687	3.1148	2.5666	4.7594	4.4201	2.5247	3.0802	5.1314	5.4263	1.7642		6.9981	6.7721	2.5173	2.5402	3.0965	8.7368	7.7353	7.9354
H19	4.2258	2.7938	5.2489	2.1658	6.6489	1.1063	7.7687	2.1701	4.4201	4.7594	2.5666	3.1148	5.4263	5.1314	3.0802	2.5247	6.7721	6.9981		1.7642	8.7368	7.9354	7.7353	2.5173	3.0965	2.5402
H20	4.2258	2.7938	5.2489	2.1658	6.6489	1.1063	7.7687	2.1701	4.7594	4.4201	3.1148	2.5666	5.1314	5.4263	2.5247	3.0802	6.9981	6.7721	1.7642		8.7368	7.7353	7.9354	2.5173	2.5402	3.0965
H21	4.7544	6.0625	3.5202	7.3175	2.1925	8.6209	1.1020	9.8764	4.9129	4.9129	6.2288	6.2288	3.7998	3.7998	7.4212	7.4212	2.5173	2.5173	8.7368	8.7368		1.7800	1.7800	10.7872	9.9975	9.9975
H22	4.2618	5.2867	2.8308	6.6841	2.1878	7.8163	1.1034	9.1811	4.7931	4.4537	5.4638	5.1687	2.6040	3.1492	6.8081	7.0347	3.0965	2.5402	7.9354	7.7353	1.7800		1.7775	9.9975	9.3120	9.4801
H23	4.2618	5.2867	2.8308	6.6841	2.1878	7.8163	1.1034	9.1811	4.4537	4.7931	5.1687	5.4638	3.1492	2.6040	7.0347	6.8081	2.5402	3.0965	7.7353	7.9354	1.7800	1.7775		9.9975	9.4801	9.3120
H24	6.0625	4.7544	7.3175	3.5202	8.6209	2.1925	9.8764	1.1020	6.2288	6.2288	4.9129	4.9129	7.4212	7.4212	3.7998	3.7998	8.7368	8.7368	2.5173	2.5173	10.7872	9.9975	9.9975		1.7800	1.7800
H25	5.2867	4.2618	6.6841	2.8308	7.8163	2.1878	9.1811	1.1034	5.4638	5.1687	4.7931	4.4537	6.8081	7.0347	2.6040	3.1492	7.9354	7.7353	3.0965	2.5402	9.9975	9.3120	9.4801	1.7800		1.7775
H26	5.2867	4.2618	6.6841	2.8308	7.8163	2.1878	9.1811	1.1034	5.1687	5.4638	4.4537	4.7931	7.0347	6.8081	3.1492	2.6040	7.7353	7.9354	2.5402	3.0965	9.9975	9.4801	9.3120	1.7800	1.7775

picture of Octane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	113.503	C1	C2	H11	109.325
C1	C2	H12	109.325	C1	C3	C5	113.687
C1	C3	H13	109.340	C1	C3	H14	109.340
C2	C1	C3	113.503	C2	C1	H9	109.325
C2	C1	H10	109.325	C2	C4	C6	113.687
C2	C4	H15	109.340	C2	C4	H16	109.340
C3	C1	H9	109.339	C3	C1	H10	109.339
C3	C5	C7	113.214	C3	C5	H17	109.161
C3	C5	H18	109.161	C4	C2	H11	109.339
C4	C2	H12	109.339	C4	C6	C8	113.214
C4	C6	H19	109.161	C4	C6	H20	109.161
C5	C3	H13	109.254	C5	C3	H14	109.254
C5	C7	H21	111.668	C5	C7	H22	111.202
C5	C7	H23	111.202	C6	C4	H15	109.254
C6	C4	H16	109.254	C6	C8	H24	111.668
C6	C8	H25	111.202	C6	C8	H26	111.202
C7	C5	H17	109.639	C7	C5	H18	109.639
C8	C6	H19	109.639	C8	C6	H20	109.639
H9	C1	H10	105.717	H11	C2	H12	105.717
H13	C3	H14	105.656	H15	C4	H16	105.656
H17	C5	H18	105.755	H19	C6	H20	105.755
H21	C7	H22	107.626	H21	C7	H23	107.626
H22	C7	H23	107.309	H24	C8	H25	107.626
H24	C8	H26	107.626	H25	C8	H26	107.309

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/6-31G(2df,p) Charges (e)

Number	Element	Mulliken
1	C	-0.202
2	C	-0.202
3	C	-0.182
4	C	-0.182
5	C	-0.190
6	C	-0.190
7	C	-0.412
8	C	-0.412
9	H	0.102
10	H	0.102
11	H	0.102
12	H	0.102
13	H	0.101
14	H	0.101
15	H	0.101
16	H	0.101
17	H	0.105
18	H	0.105
19	H	0.105
20	H	0.105
21	H	0.121
22	H	0.124
23	H	0.124
24	H	0.121
25	H	0.124
26	H	0.124

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	-55.625	0.597	0.000
y	0.597	-55.068	0.000
z	0.000	0.000	-53.478

Traceless
	x	y	z
x	-1.353	0.597	0.000
y	0.597	-0.516	0.000
z	0.000	0.000	1.869

Polar
3z²-r²	3.738
x²-y²	-0.558
xy	0.597
xz	0.000
yz	0.000

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

	x	y	z
x	14.105	-2.544	0.000
y	-2.544	15.767	0.000
z	0.000	0.000	11.754

<r²> (average value of r²) Å²

<r²>	686.075
(<r²>)^1/2	26.193

All results from a given calculation for C₈H₁₈ (Octane)

using model chemistry: PBEPBE/6-31G(2df,p)

States and conformations

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All results from a given calculation for C8H18 (Octane)

using model chemistry: PBEPBE/6-31G(2df,p)

States and conformations

All results from a given calculation for C₈H₁₈ (Octane)