Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)

Property	Value	Uncertainty	units	Reference	Comment
Hfg(298.15K)	15.50	0.80	kJ mol-1	2005Rus/Bog:573
Hfg(0K)		0.80	kJ mol-1	2005Rus/Bog:573

Information can also be found for this species in the NIST Chemistry Webbook

Vibrational levels (cm^-1)

Mode Number	Symmetry	Frequency (cm-1)	Frequency Reference	Intensity (km mol-1)	Int. unc.	Intensity Reference	Comment
1	A1	2933	webbook				2969.8 and 2861.0 Fermi resonance with 2nu5
2	A1	1252	webbook
3	A1	533	webbook
4	E	3060	webbook
5	E	1436	webbook
6	E	882	webbook

vibrational zero-point energy: 8013.2 cm^-1
Calculated vibrational frequencies for CH₃I (methyl iodide).

Rotational Constants (cm^-1)
See section I.F.4 to change rotational constant units

A	B	C	reference	comment
5.17340	0.25021	0.25021	1975mal:94

Calculated rotational constants for CH₃I (methyl iodide).

Product of moments of inertia
14791.37	amu3Å6		6.77292606649336E-116	gm3 cm6

Geometric Data

Point Group C_3v

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
rCH	1.084	0.003	1	3			1998Kuc	rs
rCI	2.136	0.002	1	2			1998Kuc	rs
aHCI	107.47	0.2	2	1	3		1998Kuc
aHCH	111.4	0.2	3	1	4			by symmetry

Cartesians

Atom	x (Å)	y (Å)	z (Å)
C1	0.0000	0.0000	-1.8100
I2	0.0000	0.0000	0.3258
H3	0.0000	1.0340	-2.1354
H4	0.8955	-0.5170	-2.1354
H5	-0.8955	-0.5170	-2.1354

Atom - Atom Distances
Distances in Å

	C1	I2	H3	H4	H5
C1		2.1358	1.0840	1.0840	1.0840
I2	2.1358		2.6696	2.6696	2.6696
H3	1.0840	2.6696		1.7909	1.7909
H4	1.0840	2.6696	1.7909		1.7909
H5	1.0840	2.6696	1.7909	1.7909

Calculated geometries for CH₃I (methyl iodide).

Experimental Bond Angles (degrees) from cartesians

atom1	atom2	atom3	angle		atom1	atom2	atom3	angle
I2	C1	H3	107.470		I2	C1	H4	107.470
I2	C1	H5	107.470		H3	C1	H4	111.396
H3	C1	H5	111.396		H4	C1	H5	111.396

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond

Bond Type	Count
C-I	1
H-C	3

Connectivity

Atom 1	Atom 2
C1	I2
C1	H3
C1	H4
C1	H5

Electronic energy levels (cm^-1)

Energy (cm-1)	Degeneracy	reference	description
0	1

Ionization Energies (eV)

Ionization Energy	I.E. unc.	vertical I.E.	v.I.E. unc.	Electron Affinity	E.A. unc.	reference
9.540	0.020			0.110	0.020	webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment
Calculated electric dipole moments for CH₃I (methyl iodide).
Electric quadrupole moment
Calculated electric quadrupole moments for CH₃I (methyl iodide).

References
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squib	reference	DOI
1975mal:94	PD Mallinson "The microwave spectrum of CH2DI" J. Molecular Spectroscopy 55, 94-107 (1975)	10.1016/0022-2852(75)90255-6
1998Kuc	K Kuchitsu(ed) "Structure of Free Polyatomic Molecules - Basic Data" Springer, Berlin, 1998
2005Rus/Bog:573	B Ruscic, JE Boggs, A Burcat,AG Csaszar,J Demaison, R Janoschek, JML Martin, ML Morton, MJ Rossi, JF Stanton, PG Szalay, PR Westmoreland, F Zabel, T Berces "IUPAC Critical Evaluation of Thermochemical Properties of Selected Radicals. Part I" J. Phys. Chem. Ref. Data, Vol. 34, No. 2, 2005, 573	10.1063/1.1724828
webbook	NIST Chemistry Webbook (http://webbook.nist.gov/chemistry)

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