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Understanding of nonlinear optical properties of CS2 from a microscopic viewpoint
Weiqi Li1, Wei Quan Tian, Xiudong Sun
1Department of Physics, Harbin Institute of Technology, Harbin 150001, China.
Abstract:
This study is to improve understanding of nonlinear optics through investigating the microstructures of carbon disulfide (CS(2)) liquid, an important nonlinear optical material. First principles methods are employed in this work to investigate the structure, vibrational spectra, and the 2nd hyperpolarizabilites of CS(2) clusters up to tetramers. Three types of molecular arrangements of clusters with different sizes are identified. The cluster conformations are prone to inter-converting under external disturbance due to the weak interactions among molecules. The correlation between the nonlinear optical properties and the conformation of CS(2) clusters are studied in detail in this work.
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