Acetic acid | SSHADE

Molecule

Name: Acetic acid

Name and identifiers

IUPAC name: Acetic acid
Secondary names: Ethanoic acid, Methanecarboxylic acid, Ethylic acid, Vinegar acid, CH3COOH, CH3CO2H, C2H4O2, AcOH
InChI: InChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4)
InChI key: QTBSBXVTEAMEQO-UHFFFAOYSA-N
CAS number: 64-19-7

Structure and atomic composition

Formula: $CH_3COOH$
Chemical formula: CH3COOH
Structural formula: [CH3]C(=O)[OH]
Charge: 0
Unpaired electrons: 0

	Atom	Name	Number
	$C$	Carbon	2
	$H$	Hydrogen	4
	$O$	Oxygen	2

Relations

no

Isotopic composition

Isotope mixture type: terrestrial abundance

Nuclear spin isomers

Spin type: equilibrated
Spin quantum numbers: 1/2 (para, E), 3/2 (ortho, A)
Equilibrium ortho/para ratio: 2 (2/1)

Molar mass: 60.052 $g/mol$
State STP: liquid
Protic: protic
Polarity: polar
Dipole: 1.7 $D$

Fundamental vibration modes

Molecule symmetry

Cs

Case

nonlinear-polyatomic

Vibrations number

18

Vibrations

Label	Mode	Bond	Symmetry	Degeneracy	Fundamental frequency	Observed frequency	Observed frequency	Harmonic frequency	Activity IR	Activity Raman	Strength	Comments
V1	stretching	$-O-H$	$A_{}'$	no	3583.0	3583.0			active	inactive	m
V2	stretching	$-C \leq H_3$	$A_{}'$	double	3051.0	3051.0			active	active	vw	degenerate with $\nu_13$
V3	stretching sym.	$-C \leq H_3$	$A_{}'$	no	2944.0	2944.0			active	inactive	vw
V4	stretching	$>C=O$	$A_{}'$	no	1788.0	1788.0			active	inactive	vs
V5	deformation	$-C \leq H_3$	$A_{}'$	double	1430.0	1430.0			active	inactive		shoulder - degenerate with $\nu_14$
V6	bending sym.	$-C \leq H_3$	$A_{}'$	no	1382.0	1382.0			active	inactive	m
V7	bending	$\eqslantgtr C-O-H$	$A_{}'$	no	1264.0	1264.0			active	inactive	m
V8	stretching	$\eqslantgtr C-O-$	$A_{}'$	no	1182.0	1182.0			active	inactive	s
V9	bending asym. in-p (rocking)	$-C \leq H_3$	$A_{}'$	no	989.0	989.0			active	inactive	m
V10	stretching	$\eqslantgtr C-C\leq$	$A_{}'$	no	847.0	847.0			active	inactive	w
V11	deformation	$O=C(-)-O-$	$A_{}'$	no	657.0	657.0			active	inactive	s
V12	deformation	$\geq C-C(-)=O$	$A_{}'$	no	581.0	581.0			active	inactive	m
V13	stretching	$-C \leq H_3$	$A$	double	2996.0	2996.0			active	active	vw	degenerate with $\nu_2$
V14	deformation	$-C \leq H_3$	$A$	double	1430.0	1430.0			active	inactive		shoulder - degenerate with $\nu_5$
V15	bending asym. in-p (rocking)	$-C \leq H_3$	$A$	double	1048.0				active	inactive	w	degenerate with $\nu_5$
V16	bending out-p	$>C=O$	$A$	no	642.0	642.0			active	inactive	s
V17	deformation	$\eqslantgtr C-O-$	$A$	no	534.0	534.0			active	inactive	m
V18	deformation	$-C \leq H_3$	$A$	no	93.0				active	inactive		czlculated frequency

Publications

Shimanouchi, 1972, Natl. Bur. Stand., 39, 1 - 160

Chemical functions and bonds

Chemical functions

	Function	Number
	$R-CH_3$	1
	$R-C(=O)-OH$	1

Chemical bonds

	Bond	Number
	$\geq C-H$	3
	$\eqslantgtr C-C\leq$	1
	$>C=O$	1
	$\eqslantgtr C-O-$	1
	$-O-H$	1