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II.A.1. (XV.A.)

Listing of experimental data for CH3C(O)OO (acetyl peroxy radical)

InChI=1S/C2H3O3/c1-2(3)5-4/h1H3 CC(O[O])=O
State Conformation
1A' CS
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment
3 A' 1850 2004von/Wil:2048      
4 A' 1427 2004von/Wil:2048      
5 A' 1372 2004von/Wil:2048      
6 A' 1160 2004von/Wil:2048      
7 A' 1106 2004von/Wil:2048      
8 A' 977 2004von/Wil:2048      
9 A' 743 2004von/Wil:2048      
10 A' 545 2004von/Wil:2048      
11 A' 500 2004von/Wil:2048      
12 A' 348 2004von/Wil:2048      
14 A" 1432 2004von/Wil:2048      
15 A" 1033 2004von/Wil:2048      

Calculated vibrational frequencies for CH3C(O)OO (acetyl peroxy radical).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment

Calculated rotational constants for CH3C(O)OO (acetyl peroxy radical).

Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6

Geometric Data
picture of acetyl peroxy radical

Point Group Cs

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees
Description Value unc. Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances bond lengths
Distances in Å

Calculated geometries for CH3C(O)OO (acetyl peroxy radical).

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-C 1
H-C 3
C-O 1
C=O 1
O-O 1

Atom 1 Atom 2
C1 C2
C1 H6
C1 H7
C1 H8
C2 O3
C2 O4
O4 O5

Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Calculated electric dipole moments for CH3C(O)OO (acetyl peroxy radical).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for CH3C(O)OO (acetyl peroxy radical).

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