Ab initio potential energy surface and microwave spectra for the H2-HCCCN complex
Miao Qin1, Hua Zhu1, Hongjun Fan2
1School of Chemistry, Sichuan University, Chengdu 610064, China and State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610064, China.
The Journal of Chemical Physics
|September 3, 2017
Summary
We developed a detailed potential energy surface for the H2-HCCCN complex, identifying key stable configurations and calculating rovibrational energy levels. These findings aid in understanding molecular interactions and predicting spectroscopic properties.
Area of Science:
- Physical Chemistry
- Quantum Chemistry
- Spectroscopy
Background:
- Understanding intermolecular forces is crucial for molecular interactions.
- Accurate potential energy surfaces are essential for predicting molecular behavior.
Purpose of the Study:
- To compute a four-dimensional ab initio potential energy surface for the H2-HCCCN complex.
- To investigate the bound states and spectroscopic properties of the H2-HCCCN system.
Main Methods:
- Coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)]-F12 method.
- Artificial neural networks for fitting the potential energy surface.
- Radial discrete variable representation/angular finite basis representation and Lanczos algorithm for rovibrational energy levels.
Main Results:
- A four-dimensional potential energy surface for H2-HCCCN was generated.
- A planar linear global minimum and a planar local minimum were identified.
- Rovibrational energy levels and spectroscopic parameters for four H2-HCCCN isotopologues were calculated.
Conclusions:
- The calculated spectroscopic parameters show good agreement with experimental data.
- The developed potential energy surface accurately describes the H2-HCCCN complex.
- This work provides a foundation for further theoretical and experimental studies of this system.
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