Abstract:
Highly accurate electronic structure calculations are often needed to supplement scant experimental
data. We report the ground
3
D
3
and some selected low lying excited/ionized states of Pt and its ions
obtained using the Fock space multireference coupled cluster method with four-component relativistic
spinors. The present work establishes the
stability
of the
2
S
1/2
state of its negative ion and reproduces
the binding energy of this state within 10 cm
1
. The first ionization potential (cm
1
) is estimated to
be 72 005, deviating from the experiment by just 200 (0.3%). We also report the magnetic hyperfine
coupling constants (
A
) of Pt and its ions. The present calculation provides the
A
value (GHz) of
the
3
D
3
state of Pt to be 5.78 exhibiting very good agreement with the experimental data of 5.70.
To our knowledge, this is the first relativistic
ab initio
calculation of the ionization potential and
magnetic hyperfine coupling constant for the neutral and ionic states of Pt at a high level of correlation
treatment.
