CCCBDB calculation results Page

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

Energy calculated at MP2/STO-3G

	hartrees
Energy at 0K	-310.205932
Energy at 298.15K	-310.225027
Nuclear repulsion energy	368.360823

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/STO-3G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3552	3097	0.00
2	A_g	3404	2968	0.00
3	A_g	3399	2964	0.00
4	A_g	3395	2960	0.00
5	A_g	3372	2940	0.00
6	A_g	1747	1523	0.00
7	A_g	1735	1513	0.00
8	A_g	1719	1499	0.00
9	A_g	1713	1493	0.00
10	A_g	1627	1419	0.00
11	A_g	1616	1409	0.00
12	A_g	1562	1362	0.00
13	A_g	1450	1264	0.00
14	A_g	1277	1113	0.00
15	A_g	1187	1035	0.00
16	A_g	1175	1025	0.00
17	A_g	1129	985	0.00
18	A_g	1012	883	0.00
19	A_g	494	431	0.00
20	A_g	288	252	0.00
21	A_g	205	179	0.00
22	A_u	3554	3099	10.70
23	A_u	3523	3072	29.65
24	A_u	3516	3065	0.37
25	A_u	3506	3057	0.01
26	A_u	1738	1515	2.76
27	A_u	1481	1291	0.07
28	A_u	1464	1276	0.01
29	A_u	1387	1209	0.12
30	A_u	1160	1012	0.22
31	A_u	979	854	0.70
32	A_u	829	723	1.18
33	A_u	786	685	6.54
34	A_u	241	210	0.00
35	A_u	158	138	0.00
36	A_u	69	60	0.00
37	A_u	46	40	0.00
38	B_g	3554	3099	0.00
39	B_g	3520	3069	0.00
40	B_g	3511	3061	0.00
41	B_g	3502	3054	0.00
42	B_g	1738	1515	0.00
43	B_g	1480	1291	0.00
44	B_g	1475	1286	0.00
45	B_g	1431	1248	0.00
46	B_g	1352	1179	0.00
47	B_g	1074	936	0.00
48	B_g	892	778	0.00
49	B_g	797	695	0.00
50	B_g	243	212	0.00
51	B_g	138	121	0.00
52	B_g	108	94	0.00
53	B_u	3552	3097	7.49
54	B_u	3404	2968	26.99
55	B_u	3401	2966	7.74
56	B_u	3397	2962	0.04
57	B_u	3372	2940	8.01
58	B_u	1747	1523	0.24
59	B_u	1742	1519	0.35
60	B_u	1727	1506	0.22
61	B_u	1714	1495	0.45
62	B_u	1626	1418	1.02
63	B_u	1598	1393	2.68
64	B_u	1510	1317	6.56
65	B_u	1389	1211	28.57
66	B_u	1228	1071	1.19
67	B_u	1188	1036	0.00
68	B_u	1135	990	0.07
69	B_u	997	870	2.32
70	B_u	492	429	0.14
71	B_u	355	310	0.09
72	B_u	82	71	0.02

Unscaled Zero Point Vibrational Energy (zpe) 60983.2 cm^-1
Scaled (by 0.8719) Zero Point Vibrational Energy (zpe) 53171.2 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/STO-3G

A	B	C
0.34466	0.01579	0.01546

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

Geometric Data calculated at MP2/STO-3G

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.000	0.782	0.000
C2	0.000	-0.782	0.000
C3	-1.447	1.376	0.000
C4	1.447	-1.376	0.000
C5	-1.447	2.940	0.000
C6	1.447	-2.940	0.000
C7	-2.890	3.532	0.000
C8	2.890	-3.532	0.000
H9	0.546	1.148	0.891
H10	0.546	1.148	-0.891
H11	-0.546	-1.148	0.891
H12	-0.546	-1.148	-0.891
H13	-1.993	1.011	-0.891
H14	-1.993	1.011	0.891
H15	1.993	-1.011	-0.891
H16	1.993	-1.011	0.891
H17	-0.901	3.305	0.891
H18	-0.901	3.305	-0.891
H19	0.901	-3.305	0.891
H20	0.901	-3.305	-0.891
H21	-2.859	4.635	0.000
H22	-3.447	3.202	-0.894
H23	-3.447	3.202	0.894
H24	2.859	-4.635	0.000
H25	3.447	-3.202	-0.894
H26	3.447	-3.202	0.894

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		1.5638	1.5639	2.5979	2.5978	3.9928	3.9887	5.1920	1.1069	1.1069	2.1945	2.1945	2.1948	2.1948	2.8246	2.8246	2.8230	2.8230	4.2785	4.2785	4.7980	4.3049	4.3049	6.1252	5.3430	5.3430
C2	1.5638		2.5979	1.5639	3.9928	2.5978	5.1920	3.9887	2.1945	2.1945	1.1069	1.1069	2.8246	2.8246	2.1948	2.1948	4.2785	4.2785	2.8230	2.8230	6.1252	5.3430	5.3430	4.7980	4.3049	4.3049
C3	1.5639	2.5979		3.9930	1.5637	5.1957	2.5941	6.5488	2.1943	2.1943	2.8241	2.8241	1.1068	1.1068	4.2802	4.2802	2.1937	2.1937	5.3115	5.3115	3.5521	2.8516	2.8516	7.3940	6.7600	6.7600
C4	2.5979	1.5639	3.9930		5.1957	1.5637	6.5488	2.5941	2.8241	2.8241	2.1943	2.1943	4.2802	4.2802	1.1068	1.1068	5.3115	5.3115	2.1937	2.1937	7.3940	6.7600	6.7600	3.5521	2.8516	2.8516
C5	2.5978	3.9928	1.5637	5.1957		6.5526	1.5595	7.7898	2.8236	2.8236	4.2795	4.2795	2.1938	2.1938	5.3130	5.3130	1.1067	1.1067	6.7302	6.7302	2.2067	2.2059	2.2059	8.7129	7.9031	7.9031
C6	3.9928	2.5978	5.1957	1.5637	6.5526		7.7898	1.5595	4.2795	4.2795	2.8236	2.8236	5.3130	5.3130	2.1938	2.1938	6.7302	6.7302	1.1067	1.1067	8.7129	7.9031	7.9031	2.2067	2.2059	2.2059
C7	3.9887	5.1920	2.5941	6.5488	1.5595	7.7898		9.1262	4.2749	4.2749	5.3092	5.3092	2.8202	2.8202	6.7278	6.7278	2.1908	2.1908	7.8675	7.8675	1.1037	1.1034	1.1034	9.9871	9.2889	9.2889
C8	5.1920	3.9887	6.5488	2.5941	7.7898	1.5595	9.1262		5.3092	5.3092	4.2749	4.2749	6.7278	6.7278	2.8202	2.8202	7.8675	7.8675	2.1908	2.1908	9.9871	9.2889	9.2889	1.1037	1.1034	1.1034
H9	1.1069	2.1945	2.1943	2.8241	2.8236	4.2795	4.2749	5.3092		1.7813	2.5422	3.1042	3.1043	2.5423	3.1508	2.5989	2.5969	3.1491	4.4670	4.8091	4.9543	4.8310	4.4894	6.2920	5.5245	5.2284
H10	1.1069	2.1945	2.1943	2.8241	2.8236	4.2795	4.2749	5.3092	1.7813		3.1042	2.5422	2.5423	3.1043	2.5989	3.1508	3.1491	2.5969	4.8091	4.4670	4.9543	4.4894	4.8310	6.2920	5.2284	5.5245
H11	2.1945	1.1069	2.8241	2.1943	4.2795	2.8236	5.3092	4.2749	2.5422	3.1042		1.7813	3.1508	2.5989	3.1043	2.5423	4.4670	4.8091	2.5969	3.1491	6.2920	5.5245	5.2284	4.9543	4.8310	4.4894
H12	2.1945	1.1069	2.8241	2.1943	4.2795	2.8236	5.3092	4.2749	3.1042	2.5422	1.7813		2.5989	3.1508	2.5423	3.1043	4.8091	4.4670	3.1491	2.5969	6.2920	5.2284	5.5245	4.9543	4.4894	4.8310
H13	2.1948	2.8246	1.1068	4.2802	2.1938	5.3130	2.8202	6.7278	3.1043	2.5423	3.1508	2.5989		1.7814	4.4690	4.8110	3.1032	2.5410	5.4926	5.1958	3.8315	2.6295	3.1777	7.4973	6.8798	7.1074
H14	2.1948	2.8246	1.1068	4.2802	2.1938	5.3130	2.8202	6.7278	2.5423	3.1043	2.5989	3.1508	1.7814		4.8110	4.4690	2.5410	3.1032	5.1958	5.4926	3.8315	3.1777	2.6295	7.4973	7.1074	6.8798
H15	2.8246	2.1948	4.2802	1.1068	5.3130	2.1938	6.7278	2.8202	3.1508	2.5989	3.1043	2.5423	4.4690	4.8110		1.7814	5.4926	5.1958	3.1032	2.5410	7.4973	6.8798	7.1074	3.8315	2.6295	3.1777
H16	2.8246	2.1948	4.2802	1.1068	5.3130	2.1938	6.7278	2.8202	2.5989	3.1508	2.5423	3.1043	4.8110	4.4690	1.7814		5.1958	5.4926	2.5410	3.1032	7.4973	7.1074	6.8798	3.8315	3.1777	2.6295
H17	2.8230	4.2785	2.1937	5.3115	1.1067	6.7302	2.1908	7.8675	2.5969	3.1491	4.4670	4.8091	3.1032	2.5410	5.4926	5.1958		1.7812	6.8507	7.0785	2.5294	3.1104	2.5478	8.8301	8.0261	7.8253
H18	2.8230	4.2785	2.1937	5.3115	1.1067	6.7302	2.1908	7.8675	3.1491	2.5969	4.8091	4.4670	2.5410	3.1032	5.1958	5.4926	1.7812		7.0785	6.8507	2.5294	2.5478	3.1104	8.8301	7.8253	8.0261
H19	4.2785	2.8230	5.3115	2.1937	6.7302	1.1067	7.8675	2.1908	4.4670	4.8091	2.5969	3.1491	5.4926	5.1958	3.1032	2.5410	6.8507	7.0785		1.7812	8.8301	8.0261	7.8253	2.5294	3.1104	2.5478
H20	4.2785	2.8230	5.3115	2.1937	6.7302	1.1067	7.8675	2.1908	4.8091	4.4670	3.1491	2.5969	5.1958	5.4926	2.5410	3.1032	7.0785	6.8507	1.7812		8.8301	7.8253	8.0261	2.5294	2.5478	3.1104
H21	4.7980	6.1252	3.5521	7.3940	2.2067	8.7129	1.1037	9.9871	4.9543	4.9543	6.2920	6.2920	3.8315	3.8315	7.4973	7.4973	2.5294	2.5294	8.8301	8.8301		1.7881	1.7881	10.8919	10.0983	10.0983
H22	4.3049	5.3430	2.8516	6.7600	2.2059	7.9031	1.1034	9.2889	4.8310	4.4894	5.5245	5.2284	2.6295	3.1777	6.8798	7.1074	3.1104	2.5478	8.0261	7.8253	1.7881		1.7870	10.0983	9.4085	9.5767
H23	4.3049	5.3430	2.8516	6.7600	2.2059	7.9031	1.1034	9.2889	4.4894	4.8310	5.2284	5.5245	3.1777	2.6295	7.1074	6.8798	2.5478	3.1104	7.8253	8.0261	1.7881	1.7870		10.0983	9.5767	9.4085
H24	6.1252	4.7980	7.3940	3.5521	8.7129	2.2067	9.9871	1.1037	6.2920	6.2920	4.9543	4.9543	7.4973	7.4973	3.8315	3.8315	8.8301	8.8301	2.5294	2.5294	10.8919	10.0983	10.0983		1.7881	1.7881
H25	5.3430	4.3049	6.7600	2.8516	7.9031	2.2059	9.2889	1.1034	5.5245	5.2284	4.8310	4.4894	6.8798	7.1074	2.6295	3.1777	8.0261	7.8253	3.1104	2.5478	10.0983	9.4085	9.5767	1.7881		1.7870
H26	5.3430	4.3049	6.7600	2.8516	7.9031	2.2059	9.2889	1.1034	5.2284	5.5245	4.4894	4.8310	7.1074	6.8798	3.1777	2.6295	7.8253	8.0261	2.5478	3.1104	10.0983	9.5767	9.4085	1.7881	1.7870

picture of Octane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	112.322	C1	C2	H11	109.315
C1	C2	H12	109.315	C1	C3	C5	112.318
C1	C3	H13	109.339	C1	C3	H14	109.339
C2	C1	C3	112.322	C2	C1	H9	109.315
C2	C1	H10	109.315	C2	C4	C6	112.318
C2	C4	H15	109.339	C2	C4	H16	109.339
C3	C1	H9	109.297	C3	C1	H10	109.297
C3	C5	C7	112.315	C3	C5	H17	109.272
C3	C5	H18	109.272	C4	C2	H11	109.297
C4	C2	H12	109.297	C4	C6	C8	112.315
C4	C6	H19	109.272	C4	C6	H20	109.272
C5	C3	H13	109.270	C5	C3	H14	109.270
C5	C7	H21	110.745	C5	C7	H22	110.701
C5	C7	H23	110.701	C6	C4	H15	109.270
C6	C4	H16	109.270	C6	C8	H24	110.745
C6	C8	H25	110.701	C6	C8	H26	110.701
C7	C5	H17	109.336	C7	C5	H18	109.336
C8	C6	H19	109.336	C8	C6	H20	109.336
H9	C1	H10	107.160	H11	C2	H12	107.160
H13	C3	H14	107.169	H15	C4	H16	107.169
H17	C5	H18	107.175	H19	C6	H20	107.175
H21	C7	H22	108.223	H21	C7	H23	108.223
H22	C7	H23	108.151	H24	C8	H25	108.223
H24	C8	H26	108.223	H25	C8	H26	108.151

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for C₈H₁₈ (Octane)

using model chemistry: MP2/STO-3G

States and conformations

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All results from a given calculation for C8H18 (Octane)

using model chemistry: MP2/STO-3G

States and conformations

All results from a given calculation for C₈H₁₈ (Octane)