Accurate and efficient prediction of double excitation energies using the particle–particle random phase approximation
The Journal of Chemical Physics,
Год журнала:
2025,
Номер
162(9)
Опубликована: Март 3, 2025
Double
excitations
are
crucial
to
understanding
numerous
chemical,
physical,
and
biological
processes,
but
accurately
predicting
them
remains
a
challenge.
In
this
work,
we
explore
the
particle–particle
random
phase
approximation
(ppRPA)
as
an
efficient
accurate
approach
for
computing
double
excitation
energies.
We
benchmark
ppRPA
using
various
exchange-correlation
functionals
21
molecular
systems
two
point
defect
systems.
Our
results
show
that
with
containing
appropriate
amounts
of
exact
exchange
provides
accuracy
comparable
high-level
wave
function
methods
such
CCSDT
CASPT2,
significantly
reduced
computational
cost.
Furthermore,
demonstrate
use
starting
from
excited
(N
−
2)-electron
state
calculated
by
ΔSCF
first
time,
well
its
application
in
bulk
periodic
These
findings
suggest
is
promising
tool
calculation
partial
energies
both
Язык: Английский
Localized Orbital Scaling Correction to Linear-Response Time-Dependent Density Functional Approximations
Journal of Chemical Theory and Computation,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 20, 2025
The
localized
orbital
scaling
correction
(LOSC)
method,
which
was
developed
for
eliminating
the
delocalization
error
in
density
functional
approximations
(DFAs),
is
extended
to
linear-response
regime
calculating
excitation
energies
with
time-dependent
theory
(TDDFT).
Corrections
exchange-correlation
kernel
are
derived
within
frozen-orbitalet
approximation.
Extensive
numerical
tests
on
various
data
sets
show
that
LOSC-DFAs
able
maintain
good
performance
of
parent
DFAs
valence
excitations
while
systematically
improving
Rydberg
and
charge-transfer
by
reducing
error.
For
excitations,
LOSC
can
produce
correct
asymptotic
behaviors
donor-acceptor
separation
R
as
well
energy
at
infinite
limit.
Moreover,
through
example
trans-polyacetylene
oligomers,
we
demonstrate
does
not
deteriorate
increasing
system
size,
holding
promise
application
bulk
systems.
Язык: Английский