Study of small chlorine‐doped potassium clusters by thermal ionization mass spectrometry

Abstract

The theoretical calculations have predicted that nonmetal-doped potassium clusters can be used in the synthesis of a new class of charge-transfer salts which can be considered as potential building blocks for the assembly of novel nanostructured material. In this work, K(n)Cl (n = 2-6) and K(n)Cl(n-1) (n = 3 and 4) clusters were produced by vaporization of a solid potassium chloride salt in a thermal ionization mass spectrometry. The ionization energies (IEs) were measured, and found to be 3.64 ± 0.20 eV for K(2)Cl, 3.67 ± 0.20 eV for K(3)Cl, 3.62 ± 0.20 eV for K(4)Cl, 3.57 ± 0.20 eV for K(5)Cl, 3.69 ± 0.20 eV for K(6)Cl, 3.71 ± 0.20 eV for K(3)Cl(2) and 3.72 ± 0.20 eV for K(4)Cl(3). The K(n)Cl(+) (n = 3-6) clusters were detected for the first time in a cluster beam generated by the thermal ionization source of modified design. Also, this work is the first to report experimentally obtained values of IEs for K(n)Cl(+) (n = 3-6) and K(n)Cl(n-1) (+) (n = 3 and 4) clusters. The ionization energies for K(n)Cl(+) and K(n)Cl(n-1) (+) clusters are much lower than the 4.34 eV of the potassium atom; hence, these clusters should be classified as 'superalkali' species.

Theoretical and experimental investigation of geometry and stability of small potassium‐iodide KnI (n = 2–6) clusters

“…Experimental setup used in this study is home‐built setup, which implies the Knudsen cell (KC) combined with surface ionization. The details are described elsewhere . Briefly, the Knudsen tantalum cell (7 mm × 6 mm with an orifice diameter 0.1 mm) is equipped with a tungsten heater positioned at the bottom of this cell.…”

Mass spectrometric production of heterogeneous metal clusters using Knudsen cell

“…Energije jonizacije, eV K 2 Cl 3,82±0,10 [23] K 3 Cl 3,67±0,20 [24] K 4 Cl 3,62±0,20 [24] K 5 Cl 3,57±0,20 [24] K 6 Cl 3,69±0,20 [24] ZAKLJUČAK Knudsenova efuziona ćelija kao reakciona komora sa otvorom na vrhu, za efuziju pare, prvi put je upotrebljena početkom XX veka za određivanje napona pare uzorka. Od tada je našla široku primenu u fizici i hemiji, pogotovu u masenoj spektrometriji radi ispitivanja kvalitativnog sastava gasovite faze, parcijanog pritiska svake pojedine gasovite komponente i promene parcijalnog pritiska sa temperaturom, čime se dobijaju podaci o identitetu molekula stvorenih u reakcijama pod neravnotežnim uslovima, kao i o uticaju vremena, temperature i gustine fluksa upadnih čestica na brzinu stvaranja novih molekula.…”

Sequential Observation of Alkali-halide Gas Phase Clusters in High Resolution TOF-MS and Prediction of Their Structures

“…Laser vaporization [1], thermal ionization sources [7], and other methods have been used to produce clusters of alkali halides. These different methods may give different results due to the different growth mechanisms.…”

“…Apart from forming stoichiometric (MX) n clusters, alkali-halides also enable the formation of nonstoichiometric (M n X or MX n ) clusters by adding single or multiple excess electrons, where, M=alkali metal atom, X=halogen nonmetal [5,6]. Non-stoichiometric clusters have been of great interest as prototypes for the study of a possible "metal-insulator" or "delocalization-localization" transition in the size evolution of clusters or with variations in the chemical composition [7]. Additionally, halogen rich X − (MX) n anionic clusters with an excess halogen anion allow us to trace how the delocalization of the extra charge from the added X − affects the geometries and electronic structures of these species [8].…”