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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Growth pattern and electronic properties of acetonitrile clusters: a density functional study
Sandeep Nigam1, Chiranjib Majumder
1Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085, India.
The Journal of Chemical Physics
|June 10, 2008
Summary
This study reveals acetonitrile clusters grow in layered patterns, stabilized by intermolecular CH...N interactions. Cyclic structures, especially three-membered rings, are key building blocks for stable acetonitrile clusters.
Area of Science:
- Computational Chemistry
- Molecular Clusters
- Chemical Physics
Background:
- Acetonitrile clusters exhibit complex growth patterns.
- Understanding intermolecular interactions is crucial for predicting cluster stability.
Purpose of the Study:
- To theoretically investigate the growth patterns and electronic properties of acetonitrile clusters.
- To identify the key interactions stabilizing these clusters.
- To analyze the stability of different cluster sizes and configurations.
Main Methods:
- Density Functional Theory (DFT) calculations.
- B3LYP/6-31++G(d,p) level of theory.
- Hessian calculations for stability verification.
Main Results:
- The lowest energy dimer adopts an antiparallel configuration.
- Cyclic ring structures are favored over dipole-stabilized structures for trimers and tetramers.
- Intermolecular CH...N interactions stabilize layered geometries.
- Three-membered rings are more stable than four-membered rings and serve as building blocks.
- Even-numbered clusters are generally more stable than odd-numbered ones, with exceptions for trimer and nonamer due to stable three-membered rings.
Conclusions:
- Acetonitrile cluster growth follows a layered pattern built from cyclic units.
- Intermolecular CH...N interactions are critical for cluster stability.
- The stability of acetonitrile clusters is influenced by the number of molecules and the formation of specific ring structures.
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