1 research outputs found
Anion Photoelectron Spectroscopy and CASSCF/CASPT2/RASSI Study of La<sub><i>n</i></sub><sup>–</sup> (<i>n</i> = 1, 3–7)
We
present a combined experimental and theoretical study of small
lanthanum clusters. The experimental photoelectron spectra of La<sub><i>n</i></sub><sup>–</sup> (<i>n</i> =
1, 3–7) were obtained using negative ion photoelectron spectroscopy.
Electron affinities for these clusters were found to be in a range
of 0.49 eV (La) to 1.5 eV (La<sub>7</sub>). Our computational <i>tour de force</i> in exploring the electronic structure and
its consequences for the lanthanum atom and its anion as well as for
lanthanum trimer and its anion shows the multiconfigurational method
and large basis set with spin–orbit corrections: CASSCF/CASPT2/RASSI/ANO-RCC-L
level of theory is needed to reproduce experimental accuracy. The
most stable structure for La<sub>3</sub><sup>–</sup> was established
to be an equilateral triangle (<sup>1</sup>A<sub>1</sub>′).
Chemical bonding analysis of the La<sub>3</sub><sup>–</sup> global minimum reveals that this is the first experimentally observed
species with d-AO double σ and π aromaticity