Pentavalent lanthanide nitride-oxides: NPrO and NPrO- complexes with N[triple bond, length as m-dash]Pr triple bonds

Shu-Xian Hu; Jiwen Jian; Jing Su; Xuan Wu; Jun Li; Mingfei Zhou

doi:10.1039/c7sc00710h

Pentavalent lanthanide nitride-oxides: NPrO and NPrO^- complexes with N[triple bond, length as m-dash]Pr triple bonds

Chem Sci. 2017 May 1;8(5):4035-4043. doi: 10.1039/c7sc00710h. Epub 2017 Mar 15.

Authors

Shu-Xian Hu^{1

2}, Jiwen Jian³, Jing Su², Xuan Wu³, Jun Li², Mingfei Zhou³

Affiliations

¹ Beijing Computational Science Research Center , Beijing 100094 , China.
² Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education , Tsinghua University , Beijing 100084 , China . Email: junli@tsinghua.edu.cn.
³ Collaborative Innovation Center of Chemistry for Energy Materials , Department of Chemistry , Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials , Fudan University , Shanghai 200433 , China . Email: mfzhou@fudan.edu.cn.

Abstract

The neutral molecule NPrO and its anion NPrO^- are produced via co-condensation of laser-ablated praseodymium atoms with nitric oxide in a solid neon matrix. Combined infrared spectroscopy and state-of-the-art quantum chemical calculations confirm that both species are pentavalent praseodymium nitride-oxides with linear structures that contain Pr[triple bond, length as m-dash]N triple bonds and Pr[double bond, length as m-dash]O double bonds. Electronic structure studies show that the neutral NPrO molecule features a 4f⁰ electron configuration and a Pr(v) oxidation state similar to that of the isoelectronic PrO₂ ⁺ ion, while its NPrO^- anion possesses a 4f¹ electron configuration and a Pr(iv) oxidation state. The neutral NPrO molecule is thus a rare lanthanide nitride-oxide species with a Pr(v) oxidation state, which follows the recent identification of the first Pr(v) oxidation state in the PrO₂ ⁺ and PrO₄ complexes (Angew. Chem. Int. Ed., 2016, 55, 6896). This finding indicates that lanthanide compounds with oxidation states of higher than +IV are richer in chemistry than previously recognized.