We
describe
the
implementation
of
Monte
Carlo
threshold
algorithm
for
molecular
crystals
as
a
method
to
provide
an
estimate
energy
barriers
separating
crystal
structures.
By
sampling
local
minima
accessible
from
multiple
starting
structures,
simulations
yield
global
picture
landscapes.
This
provides
valuable
information
on
depth
associated
with
structures
and
adds
available
structure
prediction
methods
that
are
used
anticipating
polymorphism.
present
results
applying
four
polymorphic
organic
crystals,
examine
influence
space
group
symmetry
constraints
during
simulations,
discuss
relationship
between
landscape
intermolecular
interactions
in
crystals.
National Science Review,
Journal Year:
2023,
Volume and Issue:
10(7)
Published: May 8, 2023
ABSTRACT
Crystal
structure
predictions
based
on
first-principles
calculations
have
gained
great
success
in
materials
science
and
solid
state
physics.
However,
the
remaining
challenges
still
limit
their
applications
systems
with
a
large
number
of
atoms,
especially
complexity
conformational
space
cost
local
optimizations
for
big
systems.
Here,
we
introduce
crystal
prediction
method,
MAGUS,
evolutionary
algorithm,
which
addresses
above
machine
learning
graph
theory.
Techniques
used
program
are
summarized
detail
benchmark
tests
provided.
With
intensive
tests,
demonstrate
that
on-the-fly
machine-learning
potentials
can
be
to
significantly
reduce
expensive
calculations,
decomposition
theory
efficiently
decrease
required
configurations
order
find
target
structures.
We
also
representative
this
method
several
research
topics,
including
unexpected
compounds
interior
planets
exotic
states
at
high
pressure
temperature
(superionic,
plastic,
partially
diffusive
state,
etc.);
new
functional
(superhard,
high-energy-density,
superconducting,
photoelectric
materials),
etc.
These
successful
demonstrated
MAGUS
code
help
accelerate
discovery
interesting
phenomena,
as
well
significant
value
general.
Journal of Chemical Theory and Computation,
Journal Year:
2023,
Volume and Issue:
19(14), P. 4743 - 4756
Published: April 13, 2023
We
develop
and
test
new
machine
learning
strategies
for
accelerating
molecular
crystal
structure
ranking
property
prediction
using
tools
from
geometric
deep
on
graphs.
Leveraging
developments
in
graph-based
the
availability
of
large
data
sets,
we
train
models
density
stability
which
are
accurate,
fast
to
evaluate,
applicable
molecules
widely
varying
size
composition.
Our
model,
MolXtalNet-D,
achieves
state-of-the-art
performance,
with
lower
than
2%
mean
absolute
error
a
diverse
set.
tool,
MolXtalNet-S,
correctly
discriminates
experimental
samples
synthetically
generated
fakes
is
further
validated
through
analysis
submissions
Cambridge
Structural
Database
Blind
Tests
5
6.
computationally
cheap
flexible
enough
be
deployed
within
an
existing
pipeline
both
reduce
search
space
score/filter
candidates.
Chemical Science,
Journal Year:
2022,
Volume and Issue:
14(5), P. 1252 - 1262
Published: Dec. 15, 2022
Molecular
crystals
are
important
for
many
applications,
including
energetic
materials,
organic
semiconductors,
and
the
development
commercialization
of
pharmaceuticals.
The
exchange-hole
dipole
moment
(XDM)
dispersion
model
has
shown
good
performance
in
calculation
relative
absolute
lattice
energies
molecular
crystals,
although
it
traditionally
been
applied
combination
with
plane-wave/pseudopotential
approaches.
This
limited
XDM
to
use
semilocal
functional
approximations,
which
suffer
from
delocalization
error
poor
quality
conformational
energies,
systems
a
few
hundreds
atoms
at
most
due
unfavorable
scaling.
In
this
work,
we
combine
numerical
atomic
orbitals,
enable
efficient
XDM-corrected
hybrid
functionals
crystals.
We
test
new
their
ability
predict
X23
set
13
ice
phases,
latter
being
particularly
stringent
test.
A
composite
approach
using
XDM-corrected,
25%
based
on
B86bPBE
achieves
mean
0.48
kcal
mol-1
per
molecule
0.19
total
compared
recent
diffusion
Monte-Carlo
data.
These
results
make
hybrids
not
only
far
more
computationally
than
previous
implementations,
but
also
accurate
density-functional
methods
crystal
date.
Chemistry of Materials,
Journal Year:
2023,
Volume and Issue:
35(3), P. 1373 - 1386
Published: Jan. 21, 2023
The
efficiency
of
solar
cells
may
be
improved
by
using
singlet
fission
(SF),
in
which
one
exciton
splits
into
two
triplet
excitons.
SF
occurs
molecular
crystals.
A
molecule
crystallize
more
than
form,
a
phenomenon
known
as
polymorphism.
Crystal
structure
affect
performance.
In
the
common
form
tetracene,
is
experimentally
to
slightly
endoergic.
second,
metastable
polymorph
tetracene
has
been
found
exhibit
better
Here,
we
conduct
inverse
design
crystal
packing
genetic
algorithm
(GA)
with
fitness
function
tailored
simultaneously
optimize
rate
and
lattice
energy.
property-based
GA
successfully
generates
structures
predicted
have
higher
rates
provides
insight
motifs
associated
We
find
putative
superior
performance
forms
whose
determined
experimentally.
energy
within
1.5
kJ/mol
most
stable
tetracene.
CrystEngComm,
Journal Year:
2023,
Volume and Issue:
25(6), P. 953 - 960
Published: Jan. 1, 2023
Pairing
the
XDM
dispersion
model
with
hybrid
density
functionals
shows
significant
improvements
in
computed
crystal
energy
landscapes
for
4
of
26
compounds
appearing
first
six
blind
tests
structure
prediction.
Communications Chemistry,
Journal Year:
2022,
Volume and Issue:
5(1)
Published: July 28, 2022
Polymorphism
in
molecular
crystals
has
important
consequences
for
the
control
of
materials
properties
and
our
understanding
crystallization.
Computational
methods,
including
crystal
structure
prediction,
have
provided
insight
into
polymorphism,
but
usually
been
limited
to
assessing
relative
energies
structures.
We
describe
implementation
Monte
Carlo
threshold
algorithm
as
a
method
provide
an
estimate
energy
barriers
separating
By
sampling
local
minima
accessible
from
multiple
starting
structures,
simulations
yield
global
picture
landscapes
valuable
information
on
depth
associated
with
present
results
applying
four
polymorphic
organic
crystals,
examine
influence
space
group
symmetry
constraints
during
simulations,
discuss
relationship
between
landscape
intermolecular
interactions
crystals.
Crystal Growth & Design,
Journal Year:
2023,
Volume and Issue:
23(8), P. 6149 - 6160
Published: July 17, 2023
The
synthesis
and
experimental
testing
of
energetic
materials
can
be
hazardous,
but
their
many
industrial
military
applications
necessitate
constant
research
development.
We
evaluate
computational
methods
for
predicting
the
crystal
structures
molecular
organic
crystals
from
structure
as
a
first
step
in
computationally
evaluating
materials,
which
could
guide
work.
Crystal
prediction
(CSP)
is
evaluated
on
test
set
10
with
known
structures,
initially
using
rigid-molecule,
anisotropic
atom–atom
force-field
approach,
followed
by
reoptimization
predicted
dispersion-corrected
solid-state
density
functional
theory
(DFT).
CSP
force
field
was
found
to
provide
good
results
some
molecules,
whose
are
reproduced
one
lowest-energy
predictions,
more
variable
than
typical
other
small
molecules.
Reoptimization
DFT
leads
reliable
demonstrating
an
approach
that
applied
area
discovery
The Journal of Physical Chemistry C,
Journal Year:
2023,
Volume and Issue:
127(21), P. 10398 - 10410
Published: May 22, 2023
Highly
ordered
epitaxial
interfaces
between
organic
semiconductors
are
considered
as
a
promising
avenue
for
enhancing
the
performance
of
electronic
devices
including
solar
cells
and
transistors,
thanks
to
their
well-controlled,
uniform
properties
high
carrier
mobilities.
The
structure
functionality
in
inextricably
linked
structure.
We
present
method
prediction
based
on
lattice
matching
followed
by
surface
matching,
implemented
open-source
Python
package,
Ogre.
step
produces
domain-matched
interfaces,
where
commensurability
is
achieved
with
different
integer
multiples
substrate
film
unit
cells.
In
step,
Bayesian
optimization
(BO)
used
find
interfacial
distance
registry
film.
BO
objective
function
dispersion
corrected
deep
neural
network
interatomic
potentials.
These
shown
be
qualitative
agreement
density
functional
theory
(DFT)
regarding
optimal
position
top
ranking
putative
interface
structures.
Ogre
investigate
7,7,8,8-tetracyanoquinodimethane
(TCNQ)
tetrathiafulvalene
(TTF),
whose
has
been
probed
ultraviolet
photoemission
spectroscopy
(UPS),
but
had
hitherto
unknown
[Organic
Electronics
2017,
48,
371].
that
TCNQ(001)
TTF(100)
most
stable
configuration,
closely
TCNQ(010)
TTF(100).
states,
calculated
using
DFT,
excellent
UPS,
presence
an
charge
transfer
state.
Journal of Chemical Theory and Computation,
Journal Year:
2023,
Volume and Issue:
19(24), P. 9388 - 9402
Published: Dec. 7, 2023
We
present
a
high-throughput,
end-to-end
pipeline
for
organic
crystal
structure
prediction
(CSP)─the
problem
of
identifying
the
stable
structures
that
will
form
from
given
molecule
based
only
on
its
molecular
composition.
Our
tool
uses
neural
network
potentials
to
allow
efficient
screening
and
structural
relaxation
generated
candidates.
consists
two
distinct
stages:
random
search,
whereby
candidates
are
randomly
screened,
optimization,
where
genetic
algorithm
(GA)
optimizes
this
screened
population.
assess
performance
each
stage
our
21
molecules
taken
Cambridge
Crystallographic
Data
Centre's
CSP
blind
tests.
show
search
alone
yields
matches
≈50%
targets.
then
validate
potential
full
pipeline,
making
use
GA
optimize
root-mean-square
deviation
between
experimentally
derived
structure.
With
approach,
we
able
find
≈80%
with
10–100
times
smaller
initial
population
sizes
than
when
using
search.
Lastly,
run
an
ANI
model
is
trained
small
data
set
extracted
in
Structural
Database,
generating
≈60%
By
leveraging
machine
learning
models
predict
energies
at
density
functional
theory
level,
has
approach
accuracy
ab
initio
methods
efficiency
empirical
force
fields.