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@article{WOS:001543719900002,
title = {Constructing high-ionic-conductivity solid-state electrolytes with
improved interface stability by rapid laser processing},
author = {Yuqing Liu and Stephen G Dale and Chorng Haur Sow and Puneet Gupta and Sharon Xiaodai Lim},
doi = {10.1016/j.jechem.2025.06.062},
times_cited = {6},
issn = {2095-4956},
year = {2025},
date = {2025-11-01},
journal = {JOURNAL OF ENERGY CHEMISTRY},
volume = {110},
pages = {712-727},
publisher = {ELSEVIER},
address = {RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS},
abstract = {All-solid-state batteries (ASSBs) with Li or Si anodes promise enhanced
safety and high energy densities but face challenges with complex
fabrication, stringent storage requirements, and pressure-dependent
operation. Polyethylene oxide (PEO)-based composite solid electrolytes
(CSEs) enable easy processing and flexible interfaces, supporting
pressure-free operation and reducing costs. However, their low ionic
conductivity remains a key limitation. Here, we present a rapid (similar
to 5 min) and eco-friendly laser modification strategy for
post-synthesized PEO CSEs, achieving enhanced ionic conductivity while
retaining the attributes of simple fabrication and compatibility with Li
and Si anodes under pressure-free operation. Laser engineering reduces
PEO crystallinity, introduces additional Li* coordination sites, and
improves interfacial stability through tailored solid electrolyte
interphases. The laser-modified electrolyte enables LiFePO4//Li cells to
retain 142.4 mAh g-1 after 800 cycles with 99.8 % Coulombic efficiency
at 1 C and 60 degrees C. Moreover, without stack pressure, a Si anode
paired with the laser-modified electrolyte delivers a high capacity of
1710.3 mAh g-1 with 56 % retention at 0.5 A g-1 after 50 cycles at 60
degrees C. Beyond performance enhancements, this work establishes a link
between fluorescence emission and Li* transport in CSEs. Specifically,
fluorescence shifts to shorter wavelengths correspond to shorter
molecular chain lengths and lower coordination bonds, supported by
time-dependent density functional theory calculations. These factors
give rise to improved Li* transport. This optical probe offers a
non-destructive approach for rapidly assessing electrolyte properties
and enriching electrolyte design. Overall, this work demonstrates laser
engineering as a practical post-synthetic strategy and highlights
fluorescence as a practical indicator for advancing next-generation
ASSBs. (c) 2025 Science Press and Dalian Institute of Chemical Physics,
Chinese Academy of Sciences. Published by Elsevier B.V. and Science
Press. All rights are reserved, including those for text and data
mining, AI training, and similar technologies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001510682900007,
title = {State-Specific Density Functionals for Excited States via a
Density-Driven Correlation Model},
author = {Tim Gould and Stephen G Dale and Leeor Kronik and Stefano Pittalis},
doi = {10.1103/PhysRevLett.134.228001},
times_cited = {5},
issn = {0031-9007},
year = {2025},
date = {2025-06-01},
journal = {PHYSICAL REVIEW LETTERS},
volume = {134},
number = {22},
publisher = {AMER PHYSICAL SOC},
address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},
abstract = {We present a first principles strategy for developing approximations for
excited states through ensemble density functionals. Central to our
result is the recognition that density-driven correlations (ddc's) can
be vitally important to address excited states individually through
ensembles, yet standard density-functional approximations based on
ground state physics miss ddc's altogether. To model the ddc, we exploit
the recently understood low-density limit of electrons in excited
states. The theory developments are then combined to produce a
proof-of-concept excited state approximation that resolves urgent
paradigmatic failures (double excitations, charge transfer excitations,
piecewise linearity) of existing state-of-art density-functional
approaches, directly from differences in self-consistent field
calculations; i.e., Delta SCF. In light of its observed impressive
performance, we conclude that the approach represents a major step
toward unified and accurate modeling of neutral and charged excitations.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001478048300001,
title = {Diagonalization without Diagonalization: A Direct Optimization Approach
for Solid-State Density Functional Theory},
author = {Tianbo Li and Min Lin and Stephen G Dale and Zekun Shi and Castro A H Neto and Kostya S Novoselov and Giovanni Vignale},
doi = {10.1021/acs.jctc.4c01551},
times_cited = {2},
issn = {1549-9618},
year = {2025},
date = {2025-04-01},
journal = {JOURNAL OF CHEMICAL THEORY AND COMPUTATION},
volume = {21},
number = {9},
pages = {4730-4741},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {We present a novel approach to address the challenges of variable
occupation numbers in direct optimization of density functional theory
(DFT). By parametrizing both the eigenfunctions and the occupation
matrix, our method minimizes the free energy with respect to these
parameters. As the stationary conditions require the occupation matrix
and the Kohn-Sham Hamiltonian to be simultaneously diagonalizable, this
leads to the concept of ``self-diagonalization,'' where, by assuming a
diagonal occupation matrix without loss of generality, the Hamiltonian
matrix naturally becomes diagonal at stationary points. Our method
incorporates physical constraints on both the eigenfunctions and the
occupations into the parametrization, transforming the constrained
optimization into an fully differentiable unconstrained problem, which
is solvable via gradient descent. Implemented in JAX, our method was
tested on aluminum and silicon, confirming that it achieves efficient
self-diagonalization, produces the correct Fermi-Dirac distribution of
the occupation numbers and yields band structures consistent with those
obtained with SCF eigensolver methods in Quantum Espresso.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001251191000001,
title = {Identifying and embedding transferability in data-driven representations
of chemical space},
author = {Tim Gould and Bun Chan and Stephen G Dale and Stefan Vuckovic},
doi = {10.1039/d4sc02358g},
times_cited = {19},
issn = {2041-6520},
year = {2024},
date = {2024-07-01},
journal = {CHEMICAL SCIENCE},
volume = {15},
number = {28},
pages = {11122-11133},
publisher = {ROYAL SOC CHEMISTRY},
address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS,
ENGLAND},
abstract = {Transferability, especially in the context of model generalization, is a
paradigm of all scientific disciplines. However, the rapid advancement
of machine learned model development threatens this paradigm, as it can
be difficult to understand how transferability is embedded (or missed)
in complex models developed using large training data sets. Two related
open problems are how to identify, without relying on human intuition,
what makes training data transferable; and how to embed transferability
into training data. To solve both problems for ab initio chemical
modelling, an indispensable tool in everyday chemistry research, we
introduce a transferability assessment tool (TAT) and demonstrate it on
a controllable data-driven model for developing density functional
approximations (DFAs). We reveal that human intuition in the curation of
training data introduces chemical biases that can hamper the
transferability of data-driven DFAs. We use our TAT to motivate three
transferability principles; one of which introduces the key concept of
transferable diversity. Finally, we propose data curation strategies for
general-purpose machine learning models in chemistry that identify and
embed the transferability principles.
We show that human intuition in the curation of training data introduces
biases that hamper model transferability. We introduce a transferability
assessment tool which rigorously measures and subsequently improves
transferability.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

@article{WOS:001183881800001,
title = {Size Isn't Everything: Geometric Tuning in Polycyclic Aromatic
Hydrocarbons and Its Implications for Carbon Nanodots},
author = {James M Scott and Stephen G Dale and James Mcbroom and Tim Gould and Qin Li},
doi = {10.1021/acs.jpca.3c07416},
times_cited = {2},
issn = {1089-5639},
year = {2024},
date = {2024-03-01},
journal = {JOURNAL OF PHYSICAL CHEMISTRY A},
volume = {128},
number = {11},
pages = {2003-2014},
publisher = {AMER CHEMICAL SOC},
address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
abstract = {Recent developments in light-emitting carbon nanodots and molecular
organic semiconductors have seen renewed interest in the properties of
polycyclic aromatic hydrocarbons (PAHs) as a family. The networks of
delocalized pi electrons in sp2-hybridized carbon grant PAHs
light-emissive properties right across the visible spectrum. However,
the mechanistic understanding of their emission energy has been limited
due to the ground state-focused methods of determination. This
computational chemistry work, therefore, seeks to validate existing
rules and elucidate new features and characteristics of PAHs that
influence their emissions. Predictions based on (time-dependent) density
functional theory account for the full 3-dimensional electronic
structure of ground and excited states and reveal that twisting and
near-degeneracies strongly influence emission spectra and may therefore
be used to tune the color of PAHs and, hence, carbon nanodots. We
particularly note that the influence of twisting goes beyond torsional
destabilization of the ground-state and geometric relaxation of the
excited state, with a third contribution associated with the electric
transition dipole. Symmetries and peri-condensation may also have an
effect, but this could not be statistically confirmed. In pursuing this
goal, we demonstrate that with minimal changes to molecular size, the
entire visible spectrum may be spanned by geometric modification alone;
we have also provided a first estimate of emission energy for 35
molecules currently lacking published emission spectra as well as clear
guidelines for when more sophisticated computational techniques are
required to predict the properties of PAHs accurately.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}