Royal Society of Chemistry eBooks,
Journal Year:
2024,
Volume and Issue:
unknown, P. 278 - 301
Published: Dec. 18, 2024
The
goal
of
this
Chapter
is
to
provide
examples
attesting
the
maturity
current
strategies
for
simulating
excited-state
dynamics
and
nonradiative
processes
molecules
in
gas
phase.
Such
progress
over
past
few
decades
means
that
we
are
approaching
possibility
performing
silico
photochemistry,
i.e.,
a
photochemical
experiment
taking
place
fully
on
computer
allowing
prediction
observables
–
at
least
qualitatively.
We
here
brief
survey
nonadiabatic
molecular
creation
hierarchy
methods
within
multiple
spawning
framework.
then
show
how
techniques
can
be
used
context
atmospheric
photochemistry.
The Journal of Chemical Physics,
Journal Year:
2024,
Volume and Issue:
160(16)
Published: April 25, 2024
We
present
the
result
of
our
calculations
ultrafast
electron
diffraction
(UED)
for
cyclobutanone
excited
into
S2
electronic
state,
which
is
based
on
non-adiabatic
dynamics
simulations
with
Ab
Initio
Multiple
Cloning
(AIMC)
method
structure
calculated
at
SA(3)-CASSCF(12,12)/aug-cc-pVDZ
level
theory.
The
key
features
in
UED
pattern
were
identified,
can
be
used
to
distinguish
between
reaction
pathways
observed
AIMC
dynamics,
although
there
a
significant
overlap
representative
signals
due
structural
similarity
products.
compared
experiment.
Journal of Chemical Theory and Computation,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 24, 2025
Nonadiabatic
molecular
dynamics
(NAMD)
simulations
are
crucial
for
revealing
the
underlying
mechanisms
of
photochemical
and
photophysical
processes.
Typical
NAMD
simulation
software
packages
rely
on
on-the-fly
ab
initio
electronic
structure
nonadiabatic
coupling
calculations,
thus
become
challenging
when
dealing
with
large
complex
systems.
We
here
introduce
a
new
Simulation
Package
non-Adiabatic
Dynamics
in
Extended
systems
(SPADE),
which
is
designed
to
address
limitations
traditional
surface
hopping
methods
these
problems.
By
design,
SPADE
enables
users
define
arbitrary
quasi-diabatic
Hamiltonians
through
parametrized
functions
incorporates
variety
algorithms
(e.g.,
global
flux
probabilities,
crossing
decoherence
corrections),
can
realize
efficient
reliable
without
using
couplings
at
all.
All
employed
expressions
diabatic
Hamiltonian
matrix
elements
be
flexibly
set
input
files.
mainly
written
Fortran
based
modular
design
has
great
capacity
further
implementation
methods.
used
simulate
both
model
atomistic
as
long
proper
provided.
As
demonstrations,
series
representative
models
studied
show
main
features
capabilities.
Journal of Chemical Theory and Computation,
Journal Year:
2024,
Volume and Issue:
20(2), P. 891 - 901
Published: Jan. 3, 2024
A
light–matter
hybrid
quasiparticle,
called
a
polariton,
is
formed
when
molecules
are
strongly
coupled
to
an
optical
cavity.
Recent
experiments
have
shown
that
polariton
chemistry
can
manipulate
chemical
reactions.
Polariton
collective
phenomenon,
and
its
effects
increase
with
the
number
of
in
However,
simulating
ensemble
excited
state
cavity
mode
theoretically
computationally
challenging.
advances
machine
learning
(ML)
techniques
promising
capabilities
modeling
ground-state
systems.
This
work
presents
general
protocol
predict
excited-state
properties,
such
as
energies,
transition
dipoles,
nonadiabatic
coupling
vectors
hierarchically
interacting
particle
neural
network.
ML
predictions
then
applied
compute
potential
energy
surfaces
electronic
spectra
prototype
azomethane
molecule
scenario.
These
computational
tools
provide
much-needed
framework
model
understand
many
molecules'
emerging
chemistry.
The Journal of Chemical Physics,
Journal Year:
2024,
Volume and Issue:
160(23)
Published: June 17, 2024
Understanding
the
nonadiabatic
dynamics
of
complex
systems
is
a
challenging
task
in
computational
photochemistry.
Herein,
we
present
an
efficient
and
user-friendly
quantum
mechanics/molecular
mechanics
(QM/MM)
interface
to
run
on-the-fly
dynamics.
Currently,
this
consists
independent
set
codes
designed
for
general-purpose
use.
demonstrate
ability
feasibility
QM/MM
by
integrating
it
with
our
long-term
developed
JADE
package.
Tailored
handle
processes
various
systems,
especially
condensed
phases
protein
environments,
delve
into
theories,
implementations,
applications
The
approach
established
within
framework
additive
scheme,
employing
electrostatic
embedding,
link-atom
inclusion,
charge-redistribution
schemes
treat
boundary.
Trajectory
surface-hopping
are
facilitated
using
fewest
switches
algorithm,
encompassing
classical
treatments
nuclear
electronic
motions,
respectively.
Finally,
report
simulations
two
typical
systems:
azomethane
water
retinal
chromophore
PSB3
environment.
Our
results
not
only
illustrate
power
program
but
also
reveal
important
roles
environmental
factors
processes.
The Journal of Chemical Physics,
Journal Year:
2025,
Volume and Issue:
162(8)
Published: Feb. 25, 2025
We
perform
on-the-fly
non-adiabatic
molecular
dynamics
simulations
using
the
recently
developed
spin-mapping
formalism.
Two
quantum
approaches
based
on
this
mapping
formalism,
(i)
fully
linearized
Spin-LSC
and
(ii)
partially
Spin-PLDM,
are
explored
quasi-diabatic
propagation
scheme.
have
performed
in
four
ab
initio
models
for
which
benchmark
multiple
spawning
(AIMS)
data
been
published.
find
that
spin-LSC
previously
reported
symmetric
quasi-classical
(SQC)
provide
nearly
equivalent
population
dynamics.
While
we
expected
more
involved
spin-PLDM
method
to
superior
accuracy
compared
other
mapping-based
approaches,
SQC
spin-LSC,
found
it
with
AIMS
results.
further
explore
underpinnings
of
correlation
function
by
decomposing
its
N2
density
matrix-focused
initial
conditions,
where
N
is
number
states
subsystem.
Finally,
an
approximate
form
function,
simplifies
simulation
reduces
computational
costs
from
N.
The Journal of Physical Chemistry Letters,
Journal Year:
2025,
Volume and Issue:
unknown, P. 4228 - 4235
Published: April 21, 2025
The
synthesis
of
novel
carbon
nanostructures
with
unique
topologies
expands
the
landscape
organic
molecules,
introducing
new
chemical
properties
and
potential
applications.
Carbon
nanorings,
composed
cyclic
paraphenylene
(CPP)
chains,
serve
as
a
versatile
scaffold
for
designing
materials
molecular
architectures
that
impact
their
optical
photoinduced
dynamics.
These
alter
balance
between
competing
π-conjugation
effects,
high
bending
strain
energies,
steric
hindrances
imposed
by
rearrangement
structures.
Here,
we
explore
dynamics
all-benzene
trefoil
knot
using
nonadiabatic
excited-state
We
show
how
its
absorption
spectra
can
be
modeled
particle
in
box
constrained
to
geometry,
analyze
internal
conversion
process
following
photoexcitation.
Our
findings
reveal
an
exciton
intraring
migration
governed
winding
chain,
ultimately
leading
self-trapping
at
specific
curvature
regions
knot.
This
behavior
contrasts
nondeterministic
corresponding
CPP,
where
localization
occurs
randomly
across
different
phenylene
units.
results
highlight
ability
knots
control
through
curvature,
tension,
planarization
positioning
these
promising
candidates
future
technological
precisely
manipulate
electronic
characteristics
is
essential
developing
more
efficient
devices.
Chemistry of Materials,
Journal Year:
2025,
Volume and Issue:
37(10), P. 3769 - 3775
Published: May 14, 2025
Conjugated
polymers
offer
unprecedented
chemical
tunability
for
modulating
energy
transfer
in
a
multitude
of
infrared
light
applications.
In
this
work,
we
use
combination
time-resolved
spectroscopic
experiments
and
nonadiabatic
molecular
dynamics
calculations
to
probe
the
photochemistry
nonradiative
transitions
recently
synthesized
narrow
bandgap
donor-acceptor
conjugated
polymer
based
on
alternating
cyclopentadithiophene
electronegative
benzothiadiazole
heterocycles.
Using
large-scale
semi-empirical
dynamics,
which
can
treat
large
260-atom
hexamer,
calculate
an
S5
→
S1
lifetime
34.75
fs,
is
consistent
with
our
data.
Our
simulations
suggest
that
vibronic
motions
central
carbons
functional
groups
are
predominantly
involved
transitions,
excitation
becomes
more
localized
monomer
fragment
over
time.
The
combined
work
provides
mechanistic
insight
into
functionalities
be
tuned
enhance
other
prospective
low-bandgap
materials.
Journal of Vacuum Science & Technology A Vacuum Surfaces and Films,
Journal Year:
2025,
Volume and Issue:
43(4)
Published: May 29, 2025
Electron
impact
driven
neutral
dissociation
of
molecules
that
is
important
in
low
temperature
plasma
investigated.
Despite
its
importance
for
technologies
microelectronics
manufacturing,
this
process
has
received
almost
no
attention
from
the
computational
chemistry
community,
which
decades
been
focused
on
photodissociation.
Simulations
are
performed
several
fluorinate-organic
their
lowest
triplet
state,
populated
via
electron
excitation.
Their
plasmas
recently
studied
experimentally
and
pathways
have
shown
to
differ
those
singlet
ground
state.
Rules
determine
proposed
rationalized
analysis
an
ensemble
trajectories,
highlighting
common
pathways.
These
rules
can
help
find
new
use
future
technologies,
produce
a
desired
chemical
composition
plasma,
enhancing
selectivity,
etch
rates,
environmental
benefits.
The Journal of Physical Chemistry Letters,
Journal Year:
2024,
Volume and Issue:
15(12), P. 3404 - 3411
Published: March 19, 2024
The
process
of
dissociation
for
two
hydrofluorocarbon
molecules
in
low
triplet
states
excited
by
electron
impact
plasma
is
investigated
ab
initio
molecular
dynamics
(AIMD).
interest
the
hydrofluorocarbons
motivated
their
role
etching
microelectronic
technologies.
Dissociation
very
fast,
and
reaction
products
can
be
predicted.
In
this
work,
it
was
found
that
higher
relax
into
lowest
state
within
a
few
femtoseconds
due
to
nonadiabatic
dynamics,
such
simplest
MD
on
seems
give
reasonable
estimate
channels
branching
ratios.
We
provide
evidence
existence
simple
rules
states.
For
with
double
bond,
bonds
adjacent
bond
dissociate
faster
than
other
bonds.
The Journal of Physical Chemistry Letters,
Journal Year:
2023,
Volume and Issue:
14(45), P. 10145 - 10150
Published: Nov. 4, 2023
Curved
aromatic
molecules
are
attractive
electronic
materials,
where
an
additional
internal
strain
uniquely
modifies
their
structure,
aromaticity,
dynamics,
and
optical
properties.
Helicenes
examples
of
such
twisted
conjugated
systems.
Herein,
we
analyze
the
photoinduced
dynamics
in
different
stereoisomers
a
hexapole
helicene
by
using
nonadiabatic
excited-state
molecular
simulations.
We
explore
how
changes
symmetry
structural
distortion
modulate
intramolecular
energy
redistribution.
find
that
distinct
helical
assembly
leads
to
rigid
distorted
structures
turn
impact
nonradiative
relaxation
ultimately
formation
self-trapped
exciton.
Subsequently,
value
twisting
angles
relative
central
triphenylene
core
structure
controls
global
aromaticity
localization
during
conversion
process.
Our
work
sheds
light
on
future
synthesis
novel
curved
compounds
can
be
directed
attain
specific
desired
properties
through
modulation
aromaticity.