Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
63(6)
Published: Dec. 7, 2023
For
the
first
time,
we
report
calculations
of
free
energies
activation
cracking
and
isomerization
reactions
alkenes
that
combine
several
different
electronic
structure
methods
with
molecular
dynamics
simulations.
We
demonstrate
use
a
high
level
theory
(here
Random
Phase
Approximation-RPA)
is
necessary
to
bridge
gap
between
experimental
computed
values.
These
transformations,
catalyzed
by
zeolites
proceeding
via
cationic
intermediates
transition
states,
are
building
blocks
many
chemical
transformations
for
valorization
long
chain
paraffins
originating,
e.g.,
from
plastic
waste,
vegetable
oils,
Fischer-Tropsch
waxes
or
crude
oils.
Compared
energy
barriers
at
PBE+D2
production
constrained
ab
initio
dynamics,
RPA
application
Machine
Learning
thermodynamic
Perturbation
Theory
(MLPT)
show
significant
decrease
reaction
an
increase
similar
magnitude
cracking,
yielding
unprecedented
agreement
results
obtained
experiments
kinetic
modeling.
Journal of Catalysis,
Journal Year:
2023,
Volume and Issue:
429, P. 115211 - 115211
Published: Nov. 22, 2023
A
systematic
investigation
of
hydrated
extraframework
aluminum
(EFAl)
species
interacting
with
Brønsted
acid
sites
(BAS)
in
H-ZSM-5
is
presented
to
understand
the
active
site
structure
under
catalytic
operating
conditions.
Static
models
EFAl
confined
unit
cell
show
that
isolated
BAS
protonate
neutral
form
cations.
Ab-initio
molecular
dynamics
(AIMD)
simulations
and
enhanced
sampling
performed
at
temperature
for
methanol-to-hydrocarbon
conversion
reveal
two
regimes
stable
species,
namely
[Al(OH)2]+
ion
existing
bonds
zeolite
scaffold
or
as
a
pore-guest
[Al(OH)2(H2O)2]+.
Our
results
indicate
hydrogen-bonding
plays
significant
role
BAS-EFAl
structure,
especially
higher
density
can
function
both
Bronsted
Lewis
acidic
components
alter
proton
transfer
kinetics
well
shape
selectivity
within
these
microporous
solids.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
64(1)
Published: Oct. 31, 2024
Abstract
Unraveling
the
nature
of
adsorbed
olefins
in
zeolites
is
crucial
to
understand
numerous
zeolite‐catalyzed
processes.
A
well‐grounded
theoretical
description
critically
depends
on
both
an
accurate
determination
potential
energy
surface
(PES)
and
a
reliable
account
entropic
effects
at
operating
conditions.
Herein,
we
propose
transfer
learning
approach
perform
random
phase
approximation
(RPA)
quality
enhanced
sampling
molecular
dynamics
simulations,
thereby
approaching
chemical
accuracy
exploration
PES.
The
proposed
methodology
used
investigate
isobutene
adsorption
H−SSZ−13
as
prototypical
system
estimate
relative
stability
physisorbed
olefins,
carbenium
ions
alkoxide
species
(SAS)
Brønsted‐acidic
zeolites.
We
show
that
tert
‐butyl
ion
formation
highly
endothermic
no
stabilization
observed
compared
complex
within
H−SSZ−13.
Hence,
its
predicted
concentration
lifetime
are
negligible,
making
direct
experimental
observation
unlikely.
Yet,
it
remains
shallow
minimum
free
over
whole
considered
temperature
range
(273–873
K),
being
therefore
short‐lived
reaction
intermediate
rather
than
transition
state
species.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 26, 2024
Abstract
Reticular
materials
rely
on
a
unique
building
concept
where
inorganic
and
organic
units
are
stitched
together
giving
access
to
an
almost
limitless
number
of
structured
ordered
porous
materials.
Given
the
versatility
chemical
elements,
underlying
nets,
topologies,
reticular
provide
platform
design
for
timely
technological
applications.
have
now
found
their
way
in
important
societal
applications,
like
carbon
capture
address
climate
change,
water
harvesting
extract
atmospheric
moisture
arid
environments,
clean
energy
Combining
predictions
from
computational
chemistry
with
advanced
experimental
characterization
synthesis
procedures
unlocks
strategy
synthesize
new
desired
properties
functions.
Within
this
review,
current
status
modeling
is
addressed
supplemented
topical
examples
highlighting
necessity
molecular
This
review
as
templated
study
starting
structure
realistic
material
towards
prediction
functions
At
end,
authors
perspective
past,
present
future
formulate
open
challenges
inspire
model
method
developments.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
63(6)
Published: Dec. 7, 2023
For
the
first
time,
we
report
calculations
of
free
energies
activation
cracking
and
isomerization
reactions
alkenes
that
combine
several
different
electronic
structure
methods
with
molecular
dynamics
simulations.
We
demonstrate
use
a
high
level
theory
(here
Random
Phase
Approximation-RPA)
is
necessary
to
bridge
gap
between
experimental
computed
values.
These
transformations,
catalyzed
by
zeolites
proceeding
via
cationic
intermediates
transition
states,
are
building
blocks
many
chemical
transformations
for
valorization
long
chain
paraffins
originating,
e.g.,
from
plastic
waste,
vegetable
oils,
Fischer-Tropsch
waxes
or
crude
oils.
Compared
energy
barriers
at
PBE+D2
production
constrained
ab
initio
dynamics,
RPA
application
Machine
Learning
thermodynamic
Perturbation
Theory
(MLPT)
show
significant
decrease
reaction
an
increase
similar
magnitude
cracking,
yielding
unprecedented
agreement
results
obtained
experiments
kinetic
modeling.