Formation and Electronic Structures of Organoeuropium Sandwich Nanowires

Natsuki Hosoya, Ryuta Takegami, Jun Ichi Suzumura, Keizo Yada, Ken Miyajima, Masaaki Mitsui, Mark B. Knickelbein, Satoshi Yabushita, Atsushi Nakajima

研究成果: Article査読

15 被引用数 (Scopus)


Organoeuropium sandwich clusters, comprising europium (Eu) and 1,3,5,7-cyclooctatetraene (COT) (Eun(COT)m), were produced in the gas phase using a laser vaporization synthesis method. Photoionization mass spectra revealed an exclusive Eun(COT)m formation with three compositions: m = n + 1, m = n, and m = n - 1, which, we propose, correspond to full-sandwich, half-sandwich, and inverted-sandwich structures, respectively. The charge distributions, metal-ligand bonding characteristics, and electronic structures of the clusters were comprehensively investigated by photoionization measurements of Eun(COT)m neutrals and by photoelectron spectroscopy of Eun(COT)m- and isoelectronic Ban(COT)m- anions. The results confirmed that (1) highly ionic metal-ligand bonding is formed between Eu2+ and COT2- within the sandwich structure (at the termini, ionic forms are Eu+ and COT-) and (2) size dependence of orbital energy can be explained by the Coulombic interaction of simple point charge models between the detaching electrons and dipoles/quadrupoles. When the terminus of the sandwich clusters is Eu2+, COT2-, or Eu0, the orbital energy of the electron detachment channel at the opposite terminus strongly depends on the cluster size. In this case, the molecular stack behaves as a one-dimensionally aligned dipole; otherwise, it behaves as a quadrupole, and the relationship between cluster size and electron detachment energy is much weaker. The study also reports on the 4f orbital energy in Eu ions and the formation mechanism of organoeuropium sandwich nanowires up to 12 nm in length. The nanowires are formed by successive charge transfer at the terminal part, Eu+ and COT-, which reduces the ionization energy and increases the electron affinity, respectively. (Graph Presented).

ジャーナルJournal of Physical Chemistry A
出版ステータスPublished - 2014 9月 18

ASJC Scopus subject areas

  • 物理化学および理論化学


「Formation and Electronic Structures of Organoeuropium Sandwich Nanowires」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。