Article
Chemistry, Physical
Simon Kaiser, Naresh B. Kotadiya, Roland Rohloff, Artem Fediai, Franz Symalla, Tobias Neumann, Gert-Jan A. H. Wetzelaer, Paul W. M. Blom, Wolfgang Wenzel
Summary: In amorphous organic semiconductor devices, the performance is dependent on both the material and device configuration. By calculating device characteristics from first principles, the effort of synthesizing molecules and fabricating devices can be greatly reduced. This approach of generating a digital twin of the entire device can be extended to multilayer stacks, enabling computer-designed materials and devices for systematic improvement of OLED devices.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Chemistry, Multidisciplinary
Maria Drosou, Georgia Zahariou, Dimitrios A. Pantazis
Summary: The study reveals that the tetramanganese-calcium cluster of the oxygen-evolving complex in photosystem II adopts orientational Jahn-Teller isomeric forms in the resting state, which explains previous spectroscopic observations and establishes the functional role of this isomerism in the catalytic process.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Inorganic & Nuclear
Wilken Aldair Misael, Andreï Severo Pereira Gomes
Summary: X-ray spectroscopies provide valuable insights into the electronic structures of molecules and materials due to their high selectivity and sensitivity to the chemical environment. This study presents a protocol for simulating core excited spectra using damped response time-dependent density functional theory (TD-DFT) based on the Dirac-Coulomb Hamiltonian. The results show that the simulations closely match the experimental spectra for the uranium M-4-edge and oxygen K-edge, with reasonable agreement for the L-3-edge broad spectra. The embedded model, in which the chloride ligands are replaced by an embedding potential, successfully reproduces the spectral profile for the UO2Cl4 (2-) unit.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Nobuki Inoue, Yoshihiro Watanabe, Haruyuki Nakano
Summary: The article provides theoretical discussions on issues in relativistic molecular orbital theory applied to the quantum electrodynamics (QED) Hamiltonian. Several QED Hamiltonians previously proposed are evaluated based on orbital rotation invariance, charge conjugation and time reversal invariance, and nonrelativistic limit. A new total energy expression is proposed to prevent total energy divergence caused by electron correlations. The article also reintroduces the Dirac-Hartree-Fock (DHF) and electron correlation methods based on the Hamiltonian and energy expression.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Multidisciplinary Sciences
Adil Kabylda, Valentin Vassilev-Galindo, Stefan Chmiela, Igor Poltavsky, Alexandre Tkatchenko
Summary: Machine learning force fields (MLFFs) are being optimized to enable molecular dynamics simulations with ab initio accuracy but at a fraction of the computational cost. Challenges remain in developing efficient descriptors for non-local interatomic interactions and reducing dimensionality of descriptors for enhanced applicability and interpretability. An automatized approach is proposed to reduce interatomic descriptor features while maintaining accuracy and efficiency of MLFFs. The results show the importance of non-local features in preserving overall accuracy and reducing the required features to a comparable number with local interatomic features.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
J. Dai, R. V. Krems
Summary: In this study, we utilize the design of quantum computers to generate kernels for multi-dimensional vectors, which can be used for accurate regression models of global potential energy surfaces (PESs) for polyatomic molecules. We apply Bayesian optimization to adjust the parameters of the quantum gates in order to maximize the marginal likelihood and obtain Gaussian process models with quantum kernels. The study also explores the impact of qubit entanglement on the kernels and the generalization performance of quantum Gaussian processes by extrapolating global six-dimensional PESs in the energy domain.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Geoffrey Pirard, Francesco Basso Basset, Sergio Bietti, Stefano Sanguinetti, Rinaldo Trotta, Gabriel Bester
Summary: We used atomistic, million-atom screened pseudopotential theory and experimental characterization to study self-assembled GaAs/AlxGa1-xAs(111) quantum dots. Our numerical calculations showed that random alloy disorder in the barrier can cause symmetry breaking and result in a nonzero exciton fine structure splitting (FSS). However, we found that the emission wavelength and FSS can be simultaneously tuned without affecting the radiative lifetime by varying the concentration of aluminum in the alloyed barrier. Additionally, the optical properties of the quantum dots are robust against shape elongation.
Article
Chemistry, Physical
Tom Ichibha, Yutaka Nikaido, M. Chandler Bennett, Jaron T. Krogel, Kenta Hongo, Ryo Maezono, Fernando A. Reboredo
Summary: This study developed a locality error free effective core potentials method for transition metals, which has the potential to improve the accuracy of first-principles calculations in complex materials involving transition metals.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Leonardo A. Cunha, Diptarka Hait, Richard Kang, Yuezhi Mao, Martin Head-Gordon
Summary: The core-level spectra of elements heavier than Ne exhibit significant relativistic effects. A combination of orbital-optimized density functional theory (OO-DFT) and the spin-free exact two-component (X2C) model is used to study the K-edge spectra of third-period elements. The results show that the OO-DFT/X2C approach is accurate in predicting energies and yields a low root-mean-square error compared to experiment.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Alvaro Munoz-Castro
Summary: The isostructural and isoelectronic silver cluster [Ag-25(SR)(18)](-) exhibits a more symmetrical core compared to its gold counterpart [Au-25(SR)(18)](-) due to a less tight ligand shell. The stabilizing interaction of the Ag-13 core is primarily electrostatic in nature, with bonding contributions occupying specific superatomic shells. The replacement of the S-anchor atom with Se and Te leads to a red-shift in the optical properties of [Ag-25(XMe)(18)](-) species.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Inorganic & Nuclear
Paul Jerabek, Archa Santhosh, Peter Schwerdtfeger
Summary: The crystal structure of gold(II) sulfate differs from other coinage metal(II) sulfates, with a unique Au-2(4+) ion having a close Au-Au contact. The stability of the unusual AuSO4 structure can be attributed to aurophilic interactions enabled by relativistic effects.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Maria Judit Montes de Oca-Estevez, Rita Prosmiti
Summary: Theoretical-computational studies and recent astronomical observations have shown that complexes of noble gases may be formed in the interstellar medium, leading to a wide range of research possibilities. The present study aims to contribute to the understanding of chemical bonding and electron sharing in these systems by gathering spectroscopic data for noble gas hydride cations through high-level quantum chemistry computations. This data could serve as a benchmark for future studies on these systems and higher-order cationic noble gas hydrides of astrophysical interest.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Chao-Jiang Zhang, Filiberto Ortiz-Chi, Xi-Ling Xu, Hong-Guang Xu, Gabriel Merino, Wei-Jun Zheng
Summary: The study explored the structures of C2Al4-/0 and C(2)Al(5)(-/0) using different techniques. It was found that C2Al4- has a boat-like structure consisting of a C-2 unit surrounded by four aluminum atoms. In contrast, the neutral C2Al4 species has a planar structure with two ptC units. The most stable isomer of C2Al5- adopts a D-3h symmetry with the C(2) unit interacting with five aluminum atoms.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Jipan Yu, Kang Liu, Qunyan Wu, Bin Li, Xianghe Kong, Kongqiu Hu, Lei Mei, Liyong Yuan, Zhifang Chai, Weiqun Shi
Summary: This study investigates the covalence of actinide complexes by introducing 2-phosphaethynolate anion into the precursors of uranium and thorium complexes. The synthesis and characterization of the resulting uranium and thorium phosphaethynolate species were achieved through various spectroscopic methods. Computational analyses revealed differences in covalent bond properties between the U-O bond and Th-O bond, with uranium showing more 5f orbital contribution.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Jean-Philippe Renault, Lucie Huart, Aleksandar R. Milosavljevic, John D. Bozek, Jerome Palaudoux, Jean-Michel Guigner, Laurent Marichal, Jocelyne Leroy, Frank Wien, Marie-Anne Herve Du Penhoat, Christophe Nicolas
Summary: X-ray photoelectron spectroscopy of BSA in a liquid jet provides insights into the electronic structure and charge transfer mechanisms in biological systems. The spectra show no structural damage to BSA and reveal carbon and nitrogen atoms in different chemical environments. Comparison between solid and solvated BSA shows higher sensitivity of valence bands to solvation effects. The ionization energy of solvated BSA is determined as 5.7 +/- 0.3 eV. Experimental results are compared with theoretical calculations, highlighting the role of water in hole delocalization in proteins.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Inorganic & Nuclear
M. Arif Sajjad, Peter Schwerdtfeger, John A. Harrison, Alastair J. Nielson
Summary: DFT calculations revealed significant pi-syndetic donation in a nickel(II) complex with a chelating iminophosphane ligand, where a pendant aromatic ring forms a weak agostic interaction. The study also showed that electron withdrawing groups minimally affect the agostic and pi-syndetic donations, while electron donation switches off the pi-syndetic donation. Increasing the size of the substituent ortho to the agostic carbon causes rotation of the ring and a decline in both donations.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Jan-Michael Mewes, Peter Schwerdtfeger
Summary: In this study, an indirect approach was developed to accurately calculate the absolute Gibbs energies of solid and liquid phases of Group 12 elements using a relativistic Hamiltonian, resulting in precise determination of melting and boiling points. The calculated mean absolute deviation for melting and boiling points was only 5% and 1% respectively, with confirmation of liquid aggregate state of Cn. Additionally, the results indicated that periodic trends in this group are primarily influenced by relativistic effects.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Sarah Loeffelsender, Peter Schwerdtfeger, Stefan Grimme, Jan-Michael Mewes
Summary: This study investigates phase transitions of copper, silver, and gold using Gibbs energy calculations, revealing close agreement between spin-orbit relativistic calculations and experimental values for boiling points but significant deviations for melting points. The boiling point of gold increases by about 800 K due to relativity, while the melting point remains similar, defying the typical correlation between melting point and cohesive energy.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Peter Schwerdtfeger, Antony Burrows
Summary: This study investigates the stability of the body-centered cubic (bcc) phase compared with the face-centered cubic (fcc) phase at finite pressures. The results show that the stability of the bcc phase decreases with increasing pressure. This research provides important insights into the understanding of crystal phase stability.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Inorganic & Nuclear
Paul Jerabek, Archa Santhosh, Peter Schwerdtfeger
Summary: The crystal structure of gold(II) sulfate differs from other coinage metal(II) sulfates, with a unique Au-2(4+) ion having a close Au-Au contact. The stability of the unusual AuSO4 structure can be attributed to aurophilic interactions enabled by relativistic effects.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Edison Florez, Odile R. Smits, Jan-Michael Mewes, Paul Jerabek, Peter Schwerdtfeger
Summary: This study analyzes the closed-shell flerovium to predict its solid-state properties, revealing that flerovium behaves differently from typical noble gas elements in many aspects, and highlighting issues with using density functional theory in the research.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Marit R. Fiechter, Pi A. B. Haase, Nidal Saleh, Pascale Soulard, Benoit Tremblay, Remco W. A. Havenith, Rob G. E. Timmermans, Peter Schwerdtfeger, Jeanne Crassous, Benoit Darquie, Lukas F. Pasteka, Anastasia Borschevsky
Summary: This study presents a theory-experiment investigation on the helically chiral compounds Ru(acac)(3) and Os(acac)(3) as candidates for next-generation experiments in detecting molecular parity violation (PV) in vibrational spectra. By using relativistic density functional theory calculations, optimal vibrational modes with PV effects exceeding the projected instrumental sensitivity of the ultrahigh resolution experiment being constructed at the Laboratoire de Physique des Lasers in Paris by up to two orders of magnitude were identified. Preliminary measurements of the vibrational spectrum of Ru(acac)(3) were conducted as the initial steps towards the planned experiment.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Multidisciplinary Sciences
Antony Burrows, Shaun Cooper, P. Schwerdtfeger
Summary: We introduce two convergent series expansions using Bessel functions and the number of representations of an integer as a sum of squares for N-dimensional Madelung constants, M-N(s), where s is the exponent of the Madelung series. The convergence of the Bessel function expansion is discussed in detail. Values for M-N(s) are presented for s= 1/2, 3/2, 3 and 6 up to dimension N = 20. This work extends the original analysis of N-dimensional Madelung constants by Zucker for even dimensions up to N = 8.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2022)
Article
Chemistry, Physical
Peter Schwerdtfeger
Summary: This study investigates the dependence of nuclear quadrupole coupling constants CNQC(alpha) on the fine-structure constant alpha for various diatomic gold molecules AuX (X = H, F, Cl, Br, and I) at the density functional level of theory. The results show that the electric field gradient at gold is sensitive to the density functional applied, but the derivative with respect to alpha is less sensitive. The study also estimates the upper limit for the alpha variation in time, dCNQC/dt, at 10-9 Hz/year, which exceeds the limit of high-precision spectroscopy.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Andres Robles-Navarro, Paul Jerabek, Peter Schwerdtfeger
Summary: This study investigates the differences in crystalline structures between Group 1 and Group 11 elements using relativistic density functional theory. The results show that many-body effects, vibrational contributions, and dispersion interactions play a crucial role in explaining these differences.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Physics, Fluids & Plasmas
Antony Burrows, Shaun Cooper, Peter Schwerdtfeger
Summary: We provide a general lattice sum formula for the hexagonal close packed (hcp) structure with varying c/a ratios, based on previous works by Lennard-Jones, Ingham, Kane, and Goeppert-Mayer. The lattice sum is expressed using fast converging series of Bessel functions. Our analysis reveals a slight symmetry-breaking effect and the appearance of a second metastable minimum for the (12,6) Lennard-Jones potential around the c/a ratio of 2/3, contrasting the ideal ratio of & RADIC;8/3 in the hard-sphere model. Additionally, we demonstrate that extending the (n, m) Lennard-Jones potential through analytical continuation to n, m < 3, such as the Kratzer potential (n = 2, m = 1), produces unphysical results.
Article
Chemistry, Multidisciplinary
Eduardus, Yuval Shagam, Arie Landau, Shirin Faraji, Peter Schwerdtfeger, Anastasia Borschevsky, Lukas F. Pasteka
Summary: The isotopically chiral molecular ion CHDBrI+ is a highly promising candidate for detecting parity violation in vibrational transitions. It exhibits an exceptionally large predicted parity-violating frequency shift for the hydrogen wagging mode, which has a sub-Hz natural line width and falls within the range of available lasers. In contrast, the parent neutral molecule is significantly less sensitive to parity violation. The origin of this effect has been analyzed and explained.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Eduardus, Yuval Shagam, Arie Landau, Shirin Faraji, Peter Schwerdtfeger, Anastasia Borschevsky, Lukas F. Pasteka
Summary: The isotopically chiral molecular ion CHDBrI+ is identified as a promising candidate for detecting parity violation in vibrational transitions. It exhibits a significantly higher sensitivity to parity violation compared to the parent neutral molecule. Precision vibrational spectroscopy of CHDBrI+ is feasible and offers long interrogation times due to its ability to be prepared at internally low temperatures and resistance to predissociation.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Paul Jerabek, Antony Burrows, Peter Schwerdtfeger
Summary: This study uses density functional calculations to investigate the phase transition of metallic lithium and finds that the bcc phase and fcc phase are nearly energetically degenerate, with a small activation barrier. At high temperatures, the bcc phase becomes dominant, consistent with Landau theory. This resolves the long-standing controversy about the two phases of lithium.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Bojana D. Ostojic, Branislav Stankovic, Dragana S. Dordevic, Peter Schwerdtfeger
Summary: CO2 capture, conversion and storage are important goals in environmental science. In this study, we investigate a photochemical hydride transfer reaction between benzimidazoline derivatives and CO2, which has the potential for future photochemical CO2 reduction. By analyzing the thermodynamic hydricities, activation free energies, and reaction free energies, we find that the benzimidazoline derivatives possess strong hydride donor abilities and can reduce CO2 to formate with relatively low activation energies.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
