The Journal of Physical Chemistry A,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 21, 2024
Molecules
with
Hund's
rule
violations
between
low-lying
singlet
and
triplet
states
may
enable
a
new
generation
of
fluorescent
emitters.
However,
only
few
classes
molecules
are
known
this
property
at
the
current
time.
Here,
we
use
high-throughput
screening
algorithm
FORMED
database
to
uncover
class
compounds
where
first
excited
state
violates
rule.
We
examine
bridged
[10]-
[14]annulene
perimeters
saturated
bridges,
relate
them
conjugated
polycyclic
systems
violations.
Despite
structural
similarities
related
nonalternant
hydrocarbons,
mechanism
is
different
in
these
annulene
perimeters.
two
molecular
orbital
configurations
contribute
each
state.
Consequently,
violation
can
be
unambiguously
assigned
based
on
symmetry
lowest
states.
With
several
examples
synthetically
realistic
molecules,
[14]annulenes
thus
provides
link
alternant
(azaphenalene)
violating
These
design
principles
open
avenues
for
identification
types
order
photophysically
relevant
inverted.
Nature Biotechnology,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 22, 2025
We
introduce
a
quantum–classical
generative
model
for
small-molecule
design,
specifically
targeting
KRAS
inhibitors
cancer
therapy.
apply
the
method
to
select
and
synthesize
15
proposed
molecules
that
could
notably
engage
with
therapy,
two
holding
promise
future
development
as
inhibitors.
This
work
showcases
potential
of
quantum
computing
generate
experimentally
validated
hits
compare
favorably
against
classical
models.
A
hybrid
combines
approaches
compounds
protein.
The Journal of Physical Chemistry A,
Journal Year:
2024,
Volume and Issue:
128(12), P. 2445 - 2456
Published: March 14, 2024
Molecules
with
an
inverted
energy
gap
between
their
first
singlet
and
triplet
excited
states
have
promising
applications
in
the
next
generation
of
organic
light-emitting
diode
(OLED)
materials.
Unfortunately,
such
molecules
are
rare,
only
a
handful
examples
currently
known.
High-throughput
virtual
screening
could
assist
finding
novel
classes
these
molecules,
but
current
efforts
hampered
by
high
computational
cost
required
quantum
chemical
methods.
We
present
method
based
on
semiempirical
Pariser–Parr–Pople
theory
augmented
perturbation
show
that
it
reproduces
gaps
at
fraction
employed
excited-state
calculations.
Our
study
paves
way
for
ultrahigh-throughput
inverse
design
to
accelerate
discovery
development
this
new
OLED
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
36(30)
Published: May 25, 2024
Abstract
Computational
chemistry
is
an
indispensable
tool
for
understanding
molecules
and
predicting
chemical
properties.
However,
traditional
computational
methods
face
significant
challenges
due
to
the
difficulty
of
solving
Schrödinger
equations
increasing
cost
with
size
molecular
system.
In
response,
there
has
been
a
surge
interest
in
leveraging
artificial
intelligence
(AI)
machine
learning
(ML)
techniques
silico
experiments.
Integrating
AI
ML
into
increases
scalability
speed
exploration
space.
remain,
particularly
regarding
reproducibility
transferability
models.
This
review
highlights
evolution
from,
complementing,
or
replacing
energy
property
predictions.
Starting
from
models
trained
entirely
on
numerical
data,
journey
set
forth
toward
ideal
model
incorporating
physical
laws
quantum
mechanics.
paper
also
reviews
existing
their
intertwining,
outlines
roadmap
future
research,
identifies
areas
improvement
innovation.
Ultimately,
goal
develop
architectures
capable
accurate
transferable
solutions
equation,
thereby
revolutionizing
experiments
within
materials
science.
The Journal of Physical Chemistry A,
Journal Year:
2024,
Volume and Issue:
128(12), P. 2417 - 2426
Published: March 14, 2024
We
present
a
deep
learning
model
able
to
predict
excited
singlet–triplet
gaps
with
mean
absolute
error
(MAE)
of
≈20
meV
obtain
potential
inverted
(IST)
candidates.
exploit
cutting-edge
spherical
message
passing
graph
neural
networks
designed
specifically
for
generating
3D
representations
in
molecular
learning.
In
nutshell,
the
takes
as
input
list
unsaturated
heavy
atom
Cartesian
coordinates
and
atomic
numbers,
producing
output.
exploited
available
large
data
collections
train
on
≈40,000
heterogeneous
density
functional
theory
(DFT)
geometries
ADC(2)/cc-pVDZ
gaps.
ascertain
predictive
power
from
quantitative
perspective
obtaining
predictions
test
set
≈14,000
molecules,
whose
have
been
generated
at
DFT
level
(the
same
employed
training
set),
GFN2-xTB
level,
through
Molecular
Mechanics.
notice
performance
degradation
upon
switching
lower-quality
geometries,
ones
maintaining
satisfactory
results
(MAE
≈
50
MAE
180
generalized
AMBER
force
field
geometries),
hinting
caution
when
dealing
specific
chemical
classes.
Finally,
we
verify
qualitative
point
view,
different
≈15,000
molecules
already
used
identify
new
IST
molecules.
obtained
using
both
experimental
X-ray
candidates
similar
those
provided
by
quantum
methods,
clear
hints
path
toward
improved
performance.
Inverted
singlet–triplet
gap
(INVEST)
materials
have
promising
photophysical
properties
for
optoelectronic
applications
due
to
an
inversion
of
their
lowest
singlet
(S1)
and
triplet
(T1)
excited
states.
This
results
in
exothermic
reverse
intersystem
crossing
(rISC)
process
that
potentially
enhances
harvesting,
compared
thermally
activated
delayed
fluorescence
(TADF)
emitters
with
endothermic
rISCs.
However,
the
processes
phenomena
facilitate
conversion
between
states
INVEST
are
underexplored.
We
investigate
complex
potential
energy
surfaces
(PESs)
three
heavily
studied
azaphenalene
compounds,
namely,
cyclazine,
pentazine,
heptazine
using
two
state-of-the-art
computational
methodologies,
RMS-CASPT2
SCS-ADC(2)
methods.
Our
findings
suggest
ISC
rISC
take
place
directly
S1
T1
electronic
all
compounds
through
a
minimum-energy
point
(MECP)
activation
barrier
0.11
0.58
eV
above
state
0.06
0.36
rISC.
predict
higher-lying
not
populated,
since
structures
these
energetically
accessible.
Furthermore,
conical
intersection
(CI)
ground
is
high
(between
0.4
2.0
eV)
which
makes
nonradiative
decay
back
relatively
slow
process.
demonstrate
spin-orbit
coupling
(SOC)
driving
S1-T1
enhanced
by
vibronic
possessing
vibrational
modes
proper
symmetry.
also
rationalize
experimentally
observed
anti-Kasha
emission
cyclazine
inaccessible
CI
bright
S2
dark
states,
hindering
internal
conversion.
Finally,
we
show
able
qualitatively
reproduce
features,
but
consistently
overpredict
relative
energies
structural
minima
RMS-CASPT2.
The
identification
features
elaborates
design
rules
new
improved
quantum
yields.
ACS Catalysis,
Journal Year:
2025,
Volume and Issue:
unknown, P. 4450 - 4459
Published: Feb. 28, 2025
Enantioselective
electrocatalyzed
C–H
activations
have
emerged
as
a
transformative
platform
for
the
assembly
of
value-added
chiral
organic
molecules.
Despite
recent
progress,
construction
multiple
C(sp3)-stereogenic
centers
via
C(sp3)–C(sp3)
bond
formation
has
thus
far
proven
to
be
elusive.
In
contrast,
we
herein
report
an
annulative
activation
strategy,
generating
Fsp3-rich
molecules
with
high
levels
diastereo-
and
enantioselectivity.
κ2-N,O-oxazoline
preligands
were
effectively
employed
in
enantioselective
cobalt(III)-catalyzed
reactions.
Using
DFT-derived
descriptors
regression
statistical
modeling,
performed
parametrization
study
on
modularity
preligands.
The
resulted
model
describing
ligands'
selectivity
characterized
by
key
steric,
electronic,
interaction
behaviors.
Physical Chemistry Chemical Physics,
Journal Year:
2024,
Volume and Issue:
26(20), P. 14505 - 14513
Published: Jan. 1, 2024
High-throughput
ab
initio
calculations
and
data-mining
reveal
Hund's
rule
to
prevail
across
the
chemical
space
of
small
organic
molecules
with
systematically
varying
compositions
structures.
The Journal of Physical Chemistry A,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 11, 2025
The
ground-state
spin
multiplicity
as
well
the
energy
difference
between
lowest-energy
spin-singlet
(S1)
and
spin-triplet
(T1)
excited
states
of
topologically
frustrated
organic
(diradical)
molecules
can
be
tuned
by
doping
with
a
pair
heteroatoms
(N
or
B
atoms).
We
have
thus
systematically
studied
here
set
Clar's
Goblet
derivatives
upon
controlled
substitution
at
different
C
sites,
to
alter
electronic
structure
disclose
positions
which:
(i)
becomes
closed-shell
singlet
(ii)
S1
T1
is
considerably
small
(i.e.,
below
0.1-0.2
eV
induce
triplet
exciton
recovery
thermal
effects).
This
outcome
driven
strong
correlation
effects;
therefore,
we
applied
variety
single-reference
[TD-DFT,
CIS(D),
SCS-CC2]
multireference
[CASSCF,
NEVPT2,
RAS-srDFT]
methods.
For
TD-DFT,
covered
global
hybrid
(PBE0,
M06-2X),
range-separated
(ωB97X),
double-hybrid
(PBE-QIDH,
SOS1-PBE-QIDH,
PBE0-2)
functionals
ascertain
whether
results
were
highly
dependent
on
functional
choice.
Overall,
found
that
heterosubstitution
strategy
could
largely
modify
optical
properties
pristine
diradical
system,
these
forms
constituting
new
compounds
further
optoelectronic
applications.
Advanced Optical Materials,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 5, 2025
Abstract
Here,
the
key
role
played
by
theoretical
calculations
for
molecules
presenting
an
inverted
singlet‐triplet
excited
state
(e.g.
S
1
and
T
)
energy
difference,
or
Δ
E
ST
<
0,
whose
interest
has
steadily
raised
in
recent
years
fostered
experimental
advances
showing
negative
values
a
collection
of
real‐world
systems
is
reviewed.
The
evolution
computational
efforts
from
pioneering
on
reduced
set
prototypical
covered,
to
high‐throughput
virtual
screenings
thousands
identify
new
molecular
scaffolds
tune
properties
other
than
excitation
energies,
describe
necessary
benchmarking
methods
done
parallel
along
years.
Overall,
complementarity
prompted
discovery
more
displaying
0
values,
basic
design
principles
are
rationalized
thus
reviewed
here
too,
while
allowing
at
same
time
find
which
offer
reasonable
trade‐off
between
accuracy
cost.
Chemical Science,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Jan. 1, 2024
Evolutionary
and
machine
learning
methods
have
been
successfully
applied
to
the
generation
of
molecules
materials
exhibiting
desired
properties.
The
combination
these
two
paradigms
in
inverse
design
tasks
can
yield
powerful
that
explore
massive
chemical
spaces
more
efficiently,
improving
quality
generated
compounds.
However,
such
synergistic
approaches
are
still
an
incipient
area
research
appear
underexplored
literature.
This
perspective
covers
different
ways
incorporating
into
evolutionary
frameworks,
with
overall
goal
increasing
optimization
efficiency
genetic
algorithms.
In
particular,
surrogate
models
for
faster
fitness
function
evaluation,
discriminator
control
population
diversity
on-the-fly,
based
crossover
operations,
evolution
latent
space
discussed.
further
potential
generative
is
also
assessed,
outlining
promising
directions
future
developments.