Structure and Properties of Polyfluoride F_n^–Clusters (n= 3–29)

Abstract

The electronic and geometrical structures of the neutral Fn and singly negatively charged Fn(-) polyfluorides (n = 3-29) are studied using three levels of theory: density functional theory (DFT) with generalized gradient approximation, hybrid Hartree-Fock-DFT, and hybrid HF-DFT with long-range corrections. For n > 4, each polyfluoride possesses a number of states with different geometries that are closely spaced in total energy. The geometrical structures of the lowest total energy states follow different patterns for the even-n and odd-n Fn(-) anion branches with a preference for higher symmetry geometries. The largest F29(-) anion considered is found to possess Oh symmetry. All the anions beginning with F3(-) are found to possess adiabatic and vertical electron detachment energies exceeding the electron affinities of halogen atoms and are therefore superhalogen anions. Electron affinities, energies of formation, and binding energies show oscillatory behavior as functions of the number n of fluorine atoms. The neutral Fn species are found to be barely stable and are bound by polarization forces. The Fn(-) anions, on the contrary, are quite stable toward the loss of F, F(-), and F2(-), but not to the loss of F2.

Polyhalogen and Polyinterhalogen Anions from Fluorine to Iodine

“…Higher polyfluorine anions : Thus far, higher polyfluorine anions of the form [F n ] m − with n >5 or m >1 have not been observed experimentally. However, first quantum‐chemical evaluations of the stabilities of such higher polyfluorides have been published . Unfortunately, this investigation was limited to density functional theory, which has been shown to be inadequate for polyfluorine anions …”

“…Higher polyfluorine anions: Thus far, higher polyfluorine anions of the form [F n ] mÀ with n > 5o rm > 1h ave not been observed experimentally.H owever,f irst quantum-chemical evaluations of the stabilities of such higher polyfluorides have been published. [70] Unfortunately,t his investigation was limited to density functional theory,w hich has been shown to be inadequate for polyfluorine anions. [45] [a], [60] 388 (2) [c], [24] 478 [d], [63] n s (F 3 ) 165 (35) [c], [24] 173 [d], [63] d(F 3 ) 561 b, [24] 550 [b], [60] 551 [b], [65] 547 [b], [65] 568(262) [c], [24] 588 [d], [63] n as (F 3 ) 923 [b], [65] 919 [b], [65] n s (F 3 ) + n as (F 3 ) RbF 3 460 [a], [60] 390 [e], [63] 481 [d], [63] n s (F 3 ) 188 [d], [63] d(F 3 ) 550 [b], [60] 569 [e], [63] 590 [d], [63] n as (F 3 ) [63] 488 [d], [63] n s (F 3 ) 210 [d], [63] d(F 3 ) 549 [b], [60] 562 [e],…”

Metal Cluster Models for Heterogeneous Catalysis: A Matrix‐Isolation Perspective

“…On the other hand, the clusters that are studied are predominantly small clusters. Moreover, DFT calculations on several relatively large transition metal M 12 and M 13 clusters indicate still large structural differences between neutral and charged clusters …”

Small binary iron‐carbon clusters with persistent high magnetic moments. A theoretical characterization

“…In consequence, binary iron‐carbon clusters have become an object of study thanks to the progress in theoretical methods . Several methodologies, most of them within the density functional theory (DFT), have been used for many years to study clusters made of pure iron, iron oxide, and iron‐carbon . Recently, Zheng et al did an exhaustive and chronological review of the methodologies used during the last two decades for neutral binary iron‐carbon clusters.…”