Band
Title
8587.0 cm-1: 2ν124 of 12CH4 in natural CH4 - phase I
Type
absorption
Assignments summary
Assignment Symmetry Mode Specie(s) Molecule/Atom Bond Multiplicity Degeneracy Contribution Resonance
124 combination vibration 12CH4 CH4 12C-1H
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)
8587 ± 1 - - asymmetric 4.77 ± 0.1 5.962e-04 w 30.0
8583 ± 2 - - asymmetric 2.85 ± 0.05 w 90.0 0.117
Label
124
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
ν2 (deformation)       Bond: 12C-1H
ν4 (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
slightly blended
Peak
8587 ± 1 cm-1 (peak)
Evaluation
validated
Quality
B
Shape
asymmetric
Evaluation
undefined
Method
peak intensity
Absorption coefficient
4.77 ± 0.1 cm-1
Relative intensity
5.962e-04 ± 1.25e-05
Strength
weak (w)
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
moderately blended
Peak
8583 ± 2 cm-1 (peak)
Evaluation
validated
Quality
B
Shape
asymmetric
Evaluation
undefined
Comments
other weaker modes around 8540 and 8630 cm-1 are merged in both wings
Method
peak intensity
Absorption coefficient
2.85 ± 0.05 cm-1
Strength
weak (w)
Evaluation
validated
Quality
A