**Author details**

Luxi Li and Xianbo Shi *Brookhaven National Laboratory, Upton, NY, USA*

Cherice M. Evans *Department of Chemistry, Queens College – CUNY and the Graduate Center – CUNY, New York, NY, USA*

Gary L. Findley *Chemistry Department, University of Louisiana at Monroe, Monroe, LA, USA*

## **Appendix A. Intermolecular potential parameters**

Below is a tablulated list of the intermolecular potential parameters used to simulate the absorption line shapes in the various dopant/perturber systems presented or summarized in this work [40].


*<sup>a</sup>* Two-Yukawa potential with *κ*<sup>0</sup> = 8.50 Å, *z*<sup>1</sup> = 0.90 Å−1, and *z*<sup>2</sup> = 4.25 Å−1.

#### **6. References**

28 Will-be-set-by-IN-TECH

Below is a tablulated list of the intermolecular potential parameters used to simulate the absorption line shapes in the various dopant/perturber systems presented or summarized

*ε*/*k*<sup>B</sup> (K) *re* (Å) *γ* Ref.

Ar/Ar 119.5 3.826 – [37, 38] Kr/Kr 172.7 4.031 – [38] Xe/Xe 229.0 4.552 – [38]

*<sup>a</sup>* 141.5 3.704 – [39] CF4/CF4 181.02 4.708 – [39] Xe/Ar 200.0 4.265 – [37] XeAr/Ar 195.0 4.310 – [37] Xe/CF4 199.3 4.629 – [39] CH3I/Ar 162.2 4.572 – [38] CH3I/Kr 196.7 4.676 – [38] CH3I/Xe 297.5 4.896 – [38] CH3I/CH4 195.8 4.243 – [39] CH3I/CF4 256.0 5.016 – [39] Xe 6*s*/Ar 300.0 5.20 16.00 [37] Xe 6*s*/CF4 135.0 6.55 12.25 [39] CH3I 6*s*/Ar 110.0 6.30 12.75 [38] CH3I 6*s*/Kr 245.0 6.20 11.30 [38] CH3I 6*s*/Xe 400.0 6.39 10.25 [38] CH3I 6*s*/CH4 145.0 6.55 10.10 [39] CH3I 6*s*/CF4 185.0 6.84 12.10 [39]

/Ar 400.0 4.98 16.00 [37]

/Ar 110.0 6.30 12.75 [38]

/Kr 245.0 6.20 11.30 [38]

/Xe 400.0 6.29 10.25 [38]

/CH4 145.0 6.55 10.10 [39]

/CF4 185.0 6.84 12.10 [39]

*<sup>a</sup>* Two-Yukawa potential with *κ*<sup>0</sup> = 8.50 Å, *z*<sup>1</sup> = 0.90 Å−1, and *z*<sup>2</sup> = 4.25 Å−1.

Xe(6*s*)Ar/Ar 250.0 5.25 16.00 [37]

CH3I 6*s ν*2/Ar 150.0 6.30 12.15 [38] CH3I 6*s ν*2/Kr 225.0 6.30 10.75 [38] CH3I 6*s ν*2/Xe 360.0 6.50 9.50 [38] CH3I 6*s ν*2/CH4 105.0 6.65 9.95 [39] CH3I 6*s ν*2/CF4 135.0 6.84 11.90 [39] CH3I 6*s*� *ν*2/Ar 150.0 6.30 12.15 [38] CH3I 6*s*� *ν*2/Kr 225.0 6.30 10.75 [38] CH3I 6*s*� *ν*2/Xe 360.0 6.35 9.50 [38] CH3I 6*s*� *ν*2/CH4 105.0 6.65 9.95 [39] CH3I 6*s*� *ν*2/CF4 135.0 6.84 11.90 [39]

**Appendix A. Intermolecular potential parameters**

in this work [40].

CH4/CH4

Xe 6*s*�

CH3I 6*s*�

CH3I 6*s*�

CH3I 6*s*�

CH3I 6*s*�

CH3I 6*s*�


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