Stability, Infrared Spectra and Electronic Structures of (ZrO₂)_n(n=3–6) Clusters: DFT Study

Abstract

The stability, infrared spectra and electronic structures of (ZrO 2 ) n (n＝3-6) clusters have been investigated by using density-functional theory (DFT) at B3LYP/6-31G* level. The lowest-energy structures have been recognized by considering a number of structural isomers for each cluster size. It is found that the lowest-energy (ZrO 2 ) 5 cluster is the most stable among the (ZrO 2 ) n (n＝3-6) clusters. The vibration spectra of Zr-O stretching motion from terminal oxygen atom locate between 900 and 1000 cm −1 , and the vibrational band of Zr-O-Zr-O four member ring is obtained at 600-700 cm -1 , which are in good agreement with the experimental results. Mulliken populations and NBO charges of (ZrO 2 ) n clusters indicate that the charge transfers occur between 4d orbital of Zr atoms and 2p orbital of O atoms. HOMO-LUMO gaps illustrate that chemical stabilities of the lowest-energy (ZrO 2 ) n (n＝ 3-6) clusters display an even-odd alternating pattern with increasing cluster size.

A fluorolytic sol–gel route to access an amorphous Zr fluoride catalyst: a useful tool for C–F bond activation

“…The IR bands between 600-800 cm −1 can be attributed to Zr-O vibrations, by comparing with data that have previously been calculated for Zr-O clusters. 35 Zr-F bands could not be detected as the measurement at this end…”

“…The IR bands between 600–800 cm −1 can be attributed to Zr–O vibrations, by comparing with data that have previously been calculated for Zr–O clusters. 35 Zr–F bands could not be detected as the measurement at this end was limited to 400 cm −1 . 36 The data also show bands for i Pr residues, which suggests that a complete fluorination did not occur with HF.…”

Production of Dimethyl Carbonate Using a Zirconium–Praseodymium-Based Catalyst from Methanol and Propylene Carbonate: An Experimental and DFT Study

“…ZrO 2 is a polar molecule with a dipole moment of 7.8D, while the pure ZrO 2 support has a dipole moment of 8.4D. , The presence of the Pr atom in the ZrO 2 cage resulted in an increase of the dipole moment to 11.04 D due to the extra electron cloud of 4F orbitals. The excess electron bounded by the polar bond is localized on the Pr atom.…”