Ionization energies of K₂X (X = F, Cl, Br, I) clusters

Abstract

The electronic structure and properties of dipotassiummonohalides are important for understanding the unique physical and chemical behavior of M(n)X systems. In the present study, K(2) X (here X=F, Cl, Br, I) clusters were generated in the vapor over salts of the corresponding potassium halide, using a magnetic sector thermal ionization mass spectrometer. The ionization energies obtained for K(2)F, K(2)Cl, K(2)Br, and K(2)I molecules were 3.82 ± 0.1 eV, 3.68 ± 0.1 eV, 3.95 ± 0.1 eV, and 3.92 ± 0.1, respectively. These experimental values of ionization energies for K(2) X (X=F, Br, and I) are presented for the first time. The ionization energy of K(2)Cl determined by thermal ionization corresponds to previous results obtained by photoionization mass spectrometry, and it agrees with the theoretical ionization energy calculated by the ab initio method. The presently obtained results support previous theoretical predictions that the excess electron in dipotassiummonohalide clusters is delocalized over two potassium atoms, which is characteristic for F-center clusters.

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

“…Our theoretical prediction of 7.75 eV (single point RCCSD[T]) agrees very well with the second one. The first experimental ionization energy of K 2 I, obtained by the triple surface ionization, was 3.92 ± 0.1 eV . Our present experimental result (3.98 ± 0.20 eV) is in accord with this value.…”

Do nonmetallic superalkali cations exist?

“…Mononuclear superalkalies of the type ML k+n (where L is an alkali metal atom, k is the maximal formal valence of the central atom M, and n P 1) have been the subject of numerous theoretical and experimental studies over the past three decades. Since the first superalkali cluster Li 3 O was experimentally discovered by Wu et al [7], lots of such superalkalies have been characterized, for example, FLi 2 [8], ONa 3 [3,9], NLi 4 [3], BLi 6 [4], etc. In addition to the above-mentioned traditional superalkalies, some novel superalkali species have also been proposed in recent years.…”

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

“…The present investigation of the chlorine‐doped potassium clusters is an extension of our previous studies of small halogen‐doped alkali clusters, and a continuation of our systematic study of IEs of these clusters by the thermal ionization source of modified design MS . The clusters of the type K n Cl + and K n Cl n − 1 ( n > 3) were detected for the first time simultaneously in a cluster beam generated by a potassium fluoride.…”