Comparative analysis of electronic, magnetic, catalytic properties of clusters (PS4, CrnPS4, AlnPS4, GanPS4, n = 1 ~ 3) based on density functional theory.

CONTEXT: The article presents a comparative study of the electronic, magnetic and catalytic properties of CrPS4, AlPS4, GaPS4 and their expanded structures. It is finally found that: When n = 2, 3, the internal electron mobility of the configurations is stronger than when n = 0,1. When n = 1, the five configurations, except configuration 1Cr(4), are susceptible to both electrophilic and nucleophilic reactions at the same time. The configurations are more prone to nucleophilic reactions when n = 2 and 3, and the reaction sites are mainly located on the metal atoms; the more metal atoms, the more nucleophilic reaction sites. When the M atoms in the configuration are Al and Ga atoms, there is no big difference between the contribution of metal atoms and non-metal atoms to the magnetism in the configuration, while in the configuration containing Cr atoms, the metal atoms contribute more to the magnetism and mainly originate from the d-orbitals, which has better magnetic properties and greater application value. Configuration 2Cr(4) and configuration 1Cr(2) have better catalytic and adsorption activities and are most suitable as catalysts. METHODS: In the article, based on topological principles, density functional theory, B3LYP functional and def2-tzvp basis group and Gaussian16 quantum chemistry software were used to optimise the calculations of the clusters CrPS4, AlPS4, GaPS4 and their expanded configurations, with the most stable structure selected for each cluster, and finally, with the help of Multiwfn program, the required analytical data were obtained by assisting the calculations.

[Chemical Constituents from Patrinia villosa].

Objective: To investigate the chemical constituents from the ethanol extract of Patrinia villosa. Methods: Various column chromatographic methods including silica gel and Sephadex LH-20 were used for the isolation and purification. Chemical structures were elucidated on the basis of spectroscopic analysis. Results: Six compounds were isolated and identified as 8,9-didehydro-7-hydroxydolichodial-1-dimethyl acetal ( 1), 8,9-didehydro-7-hydroxydolichodial( 2),ursolic acid( 3), 3-O-methylquercetin( 4),luteolin( 5) and kaempferol-3-O-arabinoside( 6). Conclusion: Compound 1 is a new secoiridoid,and compounds 2,4,6 are isolated from the Patrinia genus for the first time.