Band
Title
8389.0 cm-1: 2ν1+2ν4 of 12CH4 in natural CH4 - phase I
Type
absorption
Assignments summary
Assignment Symmetry Mode Specie(s) Molecule/Atom Bond Multiplicity Degeneracy Contribution Resonance
1+2ν4 combination vibration 12CH4 CH4 12C-1H
12C-1H
unknown
Characteristics summary
Peak position
(cm-1)
Center position
(cm-1)
Width
(cm-1)
Shape Asymmetry factor Peak intensity
(cm-1)
Peak intensity relative Peak strength Integrated intensity
(cm-2)
Integrated intensity relative Integrated strength Temperature
(K)
Pressure
(bar)
8389 ± 1 - - asymmetric 0.887 ± 0.02 1.109e-04 vw 30.0
8388 ± 3 - - sharp shoulder 0.4 ± 0.1 vw 90.0 0.117
Label
1+2ν4
Category
combination vibration

Evaluation

Level
fully assigned
Evaluation
validated
# Multiplicity type Degeneracy Other band
1 unknown

Vibration modes

Label (type)
1 (stretching sym.)       Bond: 12C-1H
4 (deformation)       Bond: 12C-1H
Texture
crystal

Temperature

Temperature
30.0 ± 1.0 K
Formation temperature
90.7 K
Temperature max
90.7 K
Method #1
spectrum measurement
Overlap
moderately blended
Peak
8389 ± 1 cm-1 (peak)
Evaluation
validated
Quality
B
Shape
asymmetric
Evaluation
undefined
Method
peak intensity
Absorption coefficient
0.887 ± 0.02 cm-1
Relative intensity
1.109e-04 ± 2.5e-06
Strength
very weak (vw)
Evaluation
validated
Quality
B
Texture
crystal

Temperature

Temperature
90.0 ± 1.0 K
Formation temperature
90.7 K
Temperature max
90.7 K

Pressure

Pressure
0.117 bar
Comments
Vapor pressure
Method #1
spectrum measurement
Overlap
shoulder-tail
Peak
8388 ± 3 cm-1 (other)
Evaluation
undefined
Quality
C
Shape
sharp shoulder
Evaluation
undefined
Method
extrapolated
Absorption coefficient
0.4 ± 0.1 cm-1
Strength
very weak (vw)
Evaluation
undefined
Quality
E