CCCBDB calculation results Page

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

Energy calculated at mPW1PW91/6-31+G**

	hartrees
Energy at 0K	-315.667310
Energy at 298.15K	-315.686682
Nuclear repulsion energy	374.740592

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 mPW1PW91/6-31+G**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3140	2989	0.00
2	A_g	3057	2910	0.00
3	A_g	3049	2902	0.00
4	A_g	3036	2889	0.00
5	A_g	3034	2888	0.00
6	A_g	1515	1442	0.00
7	A_g	1504	1431	0.00
8	A_g	1496	1424	0.00
9	A_g	1491	1419	0.00
10	A_g	1422	1353	0.00
11	A_g	1418	1350	0.00
12	A_g	1391	1324	0.00
13	A_g	1301	1238	0.00
14	A_g	1167	1111	0.00
15	A_g	1097	1044	0.00
16	A_g	1080	1028	0.00
17	A_g	1023	974	0.00
18	A_g	918	874	0.00
19	A_g	471	448	0.00
20	A_g	278	264	0.00
21	A_g	194	185	0.00
22	A_u	3135	2984	117.66
23	A_u	3104	2954	139.75
24	A_u	3086	2937	0.56
25	A_u	3065	2917	0.23
26	A_u	1506	1433	19.05
27	A_u	1343	1279	0.75
28	A_u	1322	1259	0.51
29	A_u	1237	1178	0.00
30	A_u	1042	992	0.26
31	A_u	882	840	0.90
32	A_u	756	720	1.42
33	A_u	733	697	5.86
34	A_u	243	232	0.00
35	A_u	160	152	0.00
36	A_u	70	66	0.00
37	A_u	46	44	0.01
38	B_g	3135	2983	0.00
39	B_g	3096	2947	0.00
40	B_g	3074	2926	0.00
41	B_g	3061	2913	0.00
42	B_g	1506	1433	0.00
43	B_g	1344	1279	0.00
44	B_g	1331	1267	0.00
45	B_g	1284	1222	0.00
46	B_g	1207	1148	0.00
47	B_g	966	920	0.00
48	B_g	807	768	0.00
49	B_g	736	700	0.00
50	B_g	246	235	0.00
51	B_g	136	130	0.00
52	B_g	109	104	0.00
53	B_u	3140	2989	79.83
54	B_u	3057	2910	94.35
55	B_u	3051	2904	170.22
56	B_u	3042	2895	19.55
57	B_u	3032	2886	1.97
58	B_u	1519	1445	17.05
59	B_u	1510	1437	2.54
60	B_u	1498	1426	1.24
61	B_u	1491	1419	0.02
62	B_u	1420	1351	9.39
63	B_u	1415	1347	0.28
64	B_u	1351	1286	0.97
65	B_u	1249	1189	0.56
66	B_u	1110	1057	6.56
67	B_u	1091	1039	0.89
68	B_u	1040	990	0.56
69	B_u	901	858	4.08
70	B_u	473	450	0.13
71	B_u	336	320	0.02
72	B_u	81	77	0.00

Unscaled Zero Point Vibrational Energy (zpe) 54326.6 cm^-1
Scaled (by 0.9518) Zero Point Vibrational Energy (zpe) 51708.0 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 mPW1PW91/6-31+G**

A	B	C
0.35944	0.01634	0.01600

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

Geometric Data calculated at mPW1PW91/6-31+G**

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.002	0.763	0.000
C2	-0.002	-0.763	0.000
C3	-1.396	1.376	0.000
C4	1.396	-1.376	0.000
C5	-1.396	2.902	0.000
C6	1.396	-2.902	0.000
C7	-2.797	3.503	0.000
C8	2.797	-3.503	0.000
H9	0.556	1.124	0.877
H10	0.556	1.124	-0.877
H11	-0.556	-1.124	0.877
H12	-0.556	-1.124	-0.877
H13	-1.950	1.015	-0.877
H14	-1.950	1.015	0.877
H15	1.950	-1.015	-0.877
H16	1.950	-1.015	0.877
H17	-0.842	3.263	0.876
H18	-0.842	3.263	-0.876
H19	0.842	-3.263	0.876
H20	0.842	-3.263	-0.876
H21	-2.766	4.597	0.000
H22	-3.363	3.188	-0.883
H23	-3.363	3.188	0.883
H24	2.766	-4.597	0.000
H25	3.363	-3.188	-0.883
H26	3.363	-3.188	0.883

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		1.5264	1.5263	2.5531	2.5554	3.9216	3.9170	5.1005	1.0984	1.0984	2.1547	2.1547	2.1550	2.1550	2.7796	2.7796	2.7802	2.7802	4.2051	4.2051	4.7280	4.2402	4.2402	6.0303	5.2616	5.2616
C2	1.5264		2.5531	1.5263	3.9216	2.5554	5.1005	3.9170	2.1547	2.1547	1.0984	1.0984	2.7796	2.7796	2.1550	2.1550	4.2051	4.2051	2.7802	2.7802	6.0303	5.2616	5.2616	4.7280	4.2402	4.2402
C3	1.5263	2.5531		3.9199	1.5265	5.1085	2.5475	6.4333	2.1547	2.1547	2.7793	2.7793	1.0985	1.0985	4.2050	4.2050	2.1529	2.1529	5.2245	5.2245	3.4999	2.8162	2.8162	7.2792	6.6521	6.6521
C4	2.5531	1.5263	3.9199		5.1085	1.5265	6.4333	2.5475	2.7793	2.7793	2.1547	2.1547	4.2050	4.2050	1.0985	1.0985	5.2245	5.2245	2.1529	2.1529	7.2792	6.6521	6.6521	3.4999	2.8162	2.8162
C5	2.5554	3.9216	1.5265	5.1085		6.4411	1.5246	7.6559	2.7823	2.7823	4.2056	4.2056	2.1538	2.1538	5.2260	5.2260	1.0974	1.0974	6.6172	6.6172	2.1786	2.1747	2.1747	8.5762	7.7791	7.7791
C6	3.9216	2.5554	5.1085	1.5265	6.4411		7.6559	1.5246	4.2056	4.2056	2.7823	2.7823	5.2260	5.2260	2.1538	2.1538	6.6172	6.6172	1.0974	1.0974	8.5762	7.7791	7.7791	2.1786	2.1747	2.1747
C7	3.9170	5.1005	2.5475	6.4333	1.5246	7.6559		8.9659	4.2039	4.2039	5.2158	5.2158	2.7709	2.7709	6.6122	6.6122	2.1556	2.1556	7.7327	7.7327	1.0937	1.0948	1.0948	9.8260	9.1375	9.1375
C8	5.1005	3.9170	6.4333	2.5475	7.6559	1.5246	8.9659		5.2158	5.2158	4.2039	4.2039	6.6122	6.6122	2.7709	2.7709	7.7327	7.7327	2.1556	2.1556	9.8260	9.1375	9.1375	1.0937	1.0948	1.0948
H9	1.0984	2.1547	2.1547	2.7793	2.7823	4.2056	4.2039	5.2158		1.7541	2.5083	3.0607	3.0611	2.5088	3.0977	2.5533	2.5553	3.0991	4.3963	4.7331	4.8847	4.7657	4.4290	6.1950	5.4376	5.1450
H10	1.0984	2.1547	2.1547	2.7793	2.7823	4.2056	4.2039	5.2158	1.7541		3.0607	2.5083	2.5088	3.0611	2.5533	3.0977	3.0991	2.5553	4.7331	4.3963	4.8847	4.4290	4.7657	6.1950	5.1450	5.4376
H11	2.1547	1.0984	2.7793	2.1547	4.2056	2.7823	5.2158	4.2039	2.5083	3.0607		1.7541	3.0977	2.5533	3.0611	2.5088	4.3963	4.7331	2.5553	3.0991	6.1950	5.4376	5.1450	4.8847	4.7657	4.4290
H12	2.1547	1.0984	2.7793	2.1547	4.2056	2.7823	5.2158	4.2039	3.0607	2.5083	1.7541		2.5533	3.0977	2.5088	3.0611	4.7331	4.3963	3.0991	2.5553	6.1950	5.1450	5.4376	4.8847	4.4290	4.7657
H13	2.1550	2.7796	1.0985	4.2050	2.1538	5.2260	2.7709	6.6122	3.0611	2.5088	3.0977	2.5533		1.7538	4.3972	4.7340	3.0585	2.5062	5.4011	5.1087	3.7765	2.5916	3.1325	7.3822	6.7744	6.9991
H14	2.1550	2.7796	1.0985	4.2050	2.1538	5.2260	2.7709	6.6122	2.5088	3.0611	2.5533	3.0977	1.7538		4.7340	4.3972	2.5062	3.0585	5.1087	5.4011	3.7765	3.1325	2.5916	7.3822	6.9991	6.7744
H15	2.7796	2.1550	4.2050	1.0985	5.2260	2.1538	6.6122	2.7709	3.0977	2.5533	3.0611	2.5088	4.3972	4.7340		1.7538	5.4011	5.1087	3.0585	2.5062	7.3822	6.7744	6.9991	3.7765	2.5916	3.1325
H16	2.7796	2.1550	4.2050	1.0985	5.2260	2.1538	6.6122	2.7709	2.5533	3.0977	2.5088	3.0611	4.7340	4.3972	1.7538		5.1087	5.4011	2.5062	3.0585	7.3822	6.9991	6.7744	3.7765	3.1325	2.5916
H17	2.7802	4.2051	2.1529	5.2245	1.0974	6.6172	2.1556	7.7327	2.5553	3.0991	4.3963	4.7331	3.0585	2.5062	5.4011	5.1087		1.7527	6.7397	6.9638	2.4990	3.0744	2.5215	8.6923	7.8986	7.7003
H18	2.7802	4.2051	2.1529	5.2245	1.0974	6.6172	2.1556	7.7327	3.0991	2.5553	4.7331	4.3963	2.5062	3.0585	5.1087	5.4011	1.7527		6.9638	6.7397	2.4990	2.5215	3.0744	8.6923	7.7003	7.8986
H19	4.2051	2.7802	5.2245	2.1529	6.6172	1.0974	7.7327	2.1556	4.3963	4.7331	2.5553	3.0991	5.4011	5.1087	3.0585	2.5062	6.7397	6.9638		1.7527	8.6923	7.8986	7.7003	2.4990	3.0744	2.5215
H20	4.2051	2.7802	5.2245	2.1529	6.6172	1.0974	7.7327	2.1556	4.7331	4.3963	3.0991	2.5553	5.1087	5.4011	2.5062	3.0585	6.9638	6.7397	1.7527		8.6923	7.7003	7.8986	2.4990	2.5215	3.0744
H21	4.7280	6.0303	3.4999	7.2792	2.1786	8.5762	1.0937	9.8260	4.8847	4.8847	6.1950	6.1950	3.7765	3.7765	7.3822	7.3822	2.4990	2.4990	8.6923	8.6923		1.7664	1.7664	10.7288	9.9465	9.9465
H22	4.2402	5.2616	2.8162	6.6521	2.1747	7.7791	1.0948	9.1375	4.7657	4.4290	5.4376	5.1450	2.5916	3.1325	6.7744	6.9991	3.0744	2.5215	7.8986	7.7003	1.7664		1.7653	9.9465	9.2672	9.4339
H23	4.2402	5.2616	2.8162	6.6521	2.1747	7.7791	1.0948	9.1375	4.4290	4.7657	5.1450	5.4376	3.1325	2.5916	6.9991	6.7744	2.5215	3.0744	7.7003	7.8986	1.7664	1.7653		9.9465	9.4339	9.2672
H24	6.0303	4.7280	7.2792	3.4999	8.5762	2.1786	9.8260	1.0937	6.1950	6.1950	4.8847	4.8847	7.3822	7.3822	3.7765	3.7765	8.6923	8.6923	2.4990	2.4990	10.7288	9.9465	9.9465		1.7664	1.7664
H25	5.2616	4.2402	6.6521	2.8162	7.7791	2.1747	9.1375	1.0948	5.4376	5.1450	4.7657	4.4290	6.7744	6.9991	2.5916	3.1325	7.8986	7.7003	3.0744	2.5215	9.9465	9.2672	9.4339	1.7664		1.7653
H26	5.2616	4.2402	6.6521	2.8162	7.7791	2.1747	9.1375	1.0948	5.1450	5.4376	4.4290	4.7657	6.9991	6.7744	3.1325	2.5916	7.7003	7.8986	2.5215	3.0744	9.9465	9.4339	9.2672	1.7664	1.7653

picture of Octane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	113.513	C1	C2	H11	109.265
C1	C2	H12	109.265	C1	C3	C5	113.664
C1	C3	H13	109.295	C1	C3	H14	109.295
C2	C1	C3	113.513	C2	C1	H9	109.265
C2	C1	H10	109.265	C2	C4	C6	113.664
C2	C4	H15	109.295	C2	C4	H16	109.295
C3	C1	H9	109.274	C3	C1	H10	109.274
C3	C5	C7	113.213	C3	C5	H17	109.178
C3	C5	H18	109.178	C4	C2	H11	109.274
C4	C2	H12	109.274	C4	C6	C8	113.213
C4	C6	H19	109.178	C4	C6	H20	109.178
C5	C3	H13	109.183	C5	C3	H14	109.183
C5	C7	H21	111.561	C5	C7	H22	111.180
C5	C7	H23	111.180	C6	C4	H15	109.183
C6	C4	H16	109.183	C6	C8	H24	111.561
C6	C8	H25	111.180	C6	C8	H26	111.180
C7	C5	H17	109.513	C7	C5	H18	109.513
C8	C6	H19	109.513	C8	C6	H20	109.513
H9	C1	H10	105.974	H11	C2	H12	105.974
H13	C3	H14	105.931	H15	C4	H16	105.931
H17	C5	H18	105.989	H19	C6	H20	105.989
H21	C7	H22	107.635	H21	C7	H23	107.635
H22	C7	H23	107.454	H24	C8	H25	107.635
H24	C8	H26	107.635	H25	C8	H26	107.454

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/6-31+G** Charges (e)

Number	Element	Mulliken
1	C	-0.247
2	C	-0.247
3	C	-0.320
4	C	-0.320
5	C	-0.185
6	C	-0.185
7	C	-0.697
8	C	-0.697
9	H	0.159
10	H	0.159
11	H	0.159
12	H	0.159
13	H	0.158
14	H	0.158
15	H	0.158
16	H	0.158
17	H	0.161
18	H	0.161
19	H	0.161
20	H	0.161
21	H	0.166
22	H	0.164
23	H	0.164
24	H	0.166
25	H	0.164
26	H	0.164

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	-56.762	0.492	0.000
y	0.492	-55.865	0.000
z	0.000	0.000	-54.107

Traceless
	x	y	z
x	-1.776	0.492	0.000
y	0.492	-0.431	0.000
z	0.000	0.000	2.207

Polar
3z²-r²	4.414
x²-y²	-0.897
xy	0.492
xz	0.000
yz	0.000

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

	x	y	z
x	14.660	-2.087	0.000
y	-2.087	15.868	0.000
z	0.000	0.000	12.097

<r²> (average value of r²) Å²

<r²>	680.251
(<r²>)^1/2	26.082

All results from a given calculation for C₈H₁₈ (Octane)

using model chemistry: mPW1PW91/6-31+G**

States and conformations

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All results from a given calculation for C8H18 (Octane)

using model chemistry: mPW1PW91/6-31+G**

States and conformations

All results from a given calculation for C₈H₁₈ (Octane)