New Relativistic Atomic Natural Orbital Basis Sets for Lanthanide Atoms with Applications to the Ce Diatom and LuF₃

Abstract

New basis sets of the atomic natural orbital (ANO) type have been developed for the lanthanide atoms La-Lu. The ANOs have been obtained from the average density matrix of the ground and lowest excited states of the atom, the positive ions, and the atom in an electric field. Scalar relativistic effects are included through the use of a Douglas-Kroll-Hess Hamiltonian. Multiconfigurational wave functions have been used with dynamic correlation included using second-order perturbation theory (CASSCF/CASPT2). The basis sets are applied in calculations of ionization energies and some excitation energies. Computed ionization energies have an accuracy better than 0.1 eV in most cases. Two molecular applications are included as illustration: the cerium diatom and the LuF3 molecule. In both cases it is shown that 4f orbitals are not involved in the chemical bond in contrast to an earlier claim for the latter molecule.

Slow Magnetic Relaxation in Chiral Helicene-Based Coordination Complex of Dysprosium

“…Twenty-one sextets, 128 quadruplets, and 107 doublets were mixed through spin-orbit coupling in RASSI-SO. All atoms were described by ANO-RCC basis sets [62][63][64] [65] employing the PBE0 hybrid functional [66,67]. The "Stuttgart/Dresden" basis sets [68] and effective core potentials were used to describe the yttrium atom, whereas all other atoms were described with the SVP basis sets [69].…”

Gaussian basis sets for molecular applications

“…[26,27] The same design principles have since been used in the development of ANO-RCC sets for the main group elements (groups 13-18), [28] the transition metal elements [including spin-orbit (SO) effects], [29] and the actinides and lanthanides (again including SO effects). [30,31] The ANO-S, ANO-L, and ANO-RCC basis sets are the standard basis sets within the MOLCAS software. [32] Recently, Neese and Valeev have presented a series of ANO basis sets that take many cues from the correlation consistent basis sets (see below).…”

Mössbauer spectroscopy for heavy elements: a relativistic benchmark study of mercury

“…The basis for the F atom was being left in uncontracted form to allow for valence polarization of the electron density around the neighboring Hg nucleus. In the scalar-relativistic DKH calculations, both the triple-f basis set of Dyall (see results in Table 5 as well as in Table C of the supporting information) and additionally also all-electron atomic natural orbital (ANO) sets for Hg and F [104][105][106] (see results in Table D in the supporting information) were employed in a completely decontracted manner.…”