Article
Optics
Y. D. Li, B. J. Chen, H. M. Zhang, C. D. Feng
Summary: Theoretical calculations were conducted to determine the local structures and EPR parameters for VO2+ and Cu2+ impurities in oxyfluoroborate glasses. The study used perturbation formulas for EPR parameters and a superposition model for crystal-field parameters correlation with tetragonal distortion. The results indicated tetragonal compression and elongation for VO6 and CuO6 clusters in OFG, as well as determination of EPR parameter signs for VO2+ and Cu2+ centers.
JOURNAL OF LUMINESCENCE
(2021)
Article
Chemistry, Physical
Deng-Hua Li, Zhen-Yi Jiang, Yan-Min Lin, Ji-Ming Zheng
Summary: The study used first-principles DFT+U method to investigate the doping effects of Sn/Pb atoms in TiO2 anatase phase. Results showed that Sn atoms preferentially replace internal titanium atoms, while Pb atoms are more likely to substitute surface titanium atoms. The presence of tin ions and lead ions creates electron traps, delaying the recombination time of photogenerated electron-hole pairs and playing a key role in photocatalytic performance.
APPLIED SURFACE SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Jinyong Mo, Xiubing Liang, Baolong Shen, Yixing Wan, Huahai Mao, Zhibin Zhang, Wei Li, Stephan Schonecker, Levente Vitos, Xiaoqing Li
Summary: This study investigates the properties of the NbMoTaWHfx alloy series using first-principles simulations, thermodynamic modeling, and experimental techniques. Results show that Hf alloying enhances lattice distortions in the BCC NbMoTaWHfx solid solutions. X-ray diffraction reveals that alloys with Hf content ≤0.92 are single phase BCC alloys, while alloys with Hf content 1.33 and 1.82 exhibit a dual-phase BCC microstructure. Mechanical tests indicate that the addition of Hf significantly increases yield and ultimate strengths, with saturation occurring for Hf content >0.92, while compressive plasticity is slightly improved but remains limited.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Materials Science, Ceramics
Chang-Chun Ding, Meng-Jia Zhang, Wei Jin
Summary: The EPR parameters and local structure properties of the Cu2+ center in xCaF(2)-20TeO(2)-(79-x)Na2B4O7-CuO glasses were theoretically studied, with the variation tendencies and fluctuations linked to the presence of non bridging oxygen. The concentration dependences were illustrated through the transformation of BO3 and TeO3 units, leading to a decrease in covalency and increased ionicity around Cu2+.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2022)
Article
Physics, Condensed Matter
P. Fornasini, R. Grisenti, M. Dapiaggi, G. Agostini
Summary: The study indicates that there is a local rhombohedral distortion of Sn in SnTe in the temperature range from 5 to 480 K, even above 300 K. The anomalous behavior of the third and fourth EXAFS cumulants at and above 300 K may be related to the softening of high frequency modes or the presence of multiple phases.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Engineering, Electrical & Electronic
Priyanka Yadav, Sumit Sarkar, Manju Sharma, Deodatta Moreshwar Phase, Ram Janay Choudhary, Rajamani Raghunathan
Summary: Na2IrO3 (NIO) is a spin-orbit (SO) driven j = 1/2 pseudo-spin Mott-Hubbard (M-H) insulator. The mixing of j = 1/2 pseudo-spin derived from t2g orbitals with the eg orbitals has not been probed yet from the viewpoint of local structural distortions. Using a combination of theoretical calculations and X-ray spectroscopy, this study reveals the energetic factors governing the electronic behavior of NIO and rules out the possibility of a Slater insulator phase.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Physical
Yuji Ikeda, Konstantin Gubaev, Jorg Neugebauer, Blazej Grabowski, Fritz Kormann
Summary: Recent experiments have shown that the chemical composition of body-centered cubic (bcc) refractory high entropy alloys (HEAs) can be adjusted to enhance transformation-induced plasticity (TRIP), leading to improved ductility. A method utilizing symmetry analysis and ab initio calculations has been developed to identify the impact of local lattice distortions on the phase stability of HEAs.
NPJ COMPUTATIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Sahil Tippireddy, Feridoon Azough, Vikram, Animesh Bhui, Philip Chater, Demie Kepaptsoglou, Quentin Ramasse, Robert Freer, Ricardo Grau-Crespo, Kanishka Biswas, Paz Vaqueiro, Anthony Powell
Summary: Partial substitution of germanium in chalcopyrite leads to an enhancement of thermoelectric properties due to local structural distortion, lattice softening, and the appearance of resonant phonon modes. The weak chemical bonding of germanium with sulphur also contributes to a high Seebeck coefficient and an improvement in the power factor.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Inorganic & Nuclear
Rajak Syed, Anitha Mallavarapu, V. Sudarsan, Sandeep Kumar Agarwalla, Dhruva Kumar Singh, Vivekanand Kain
Summary: Ytterbium and erbium co-doped lanthanum gallate (LaGaO3) up-conversion phosphors were synthesized using polyol method and heating process. Increasing annealing temperature from 1000°C to 1200°C resulted in higher green to red ratio (GRR) and lifetime values, attributed to the increase in crystallite size and decrease in non-radiative processes. Variations in n values accounted for the increase in GRR values with higher laser power in samples annealed at 1000°C and 1200°C.
SOLID STATE SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
Jin-Gyu Bae, Ju-Hyeon Lee, Min Sung Kim, Byung Gon Kim, Hyeon Jeong Lee, Ji Hoon Lee
Summary: A molten salt synthesis method was used to produce sphere-like single-crystal magnesium-doped LiCoO2. The lattice strain was effectively alleviated, and the phase transition was suppressed by both the particle shape and Mg doping. The preference for Mg doping in the Co site rather than the Li site in the LCO framework was systematically revealed.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Samiul Islam, Suparna Tripathi, Anowar Hossain, Saikat Kumar Seth, Subrata Mukhopadhyay
Summary: This study reports the synthesis of two new complexes through a pH-dependent reaction and characterizes their structures using X-ray diffraction analysis and intermolecular interaction analysis.
JOURNAL OF MOLECULAR STRUCTURE
(2022)
Article
Chemistry, Physical
Yanlan Sun, Xuefeng Liu, Wenjing Wang, Yaohua Yang, Weiliang Zhang
Summary: Crystal defect-induced elemental diffusion is crucial for achieving metallurgical bonding. However, the interaction between immiscible element diffusion and crystal defect annihilation is not well understood. In this study, in-situ heat treatment experiments were conducted to investigate the phenomenon of immiscible element diffusion and crystal defect annihilation at the steel/Mg composite interface. The results revealed a one-way selective diffusion effect, where Mg diffused into the steel side but Fe diffusion into Mg was not significant. The study provides theoretical guidance for promoting element diffusion at immiscible metals composite interfaces.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Physics, Applied
Xiangyang Liu, Xinsheng Liu, Yiran Wang, Miao Liang, Chaoran Qin, Leshuai Sun, Chaofan Yan
Summary: Tin oxide has been widely used in perovskite solar cells as an alternative to titanium dioxide, with metal-doping and functional molecules playing important roles in optimizing film and enhancing device performance. In some experiments, metformin and urea were used to passivate interface traps, with metformin showing stronger interactions. Additionally, diblock polymers were incorporated to improve stability and performance.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Siyi Liu, Longshan Zhu, Wanshan Cao, Peiding Li, Zhuolin Zhan, Zihang Chen, Xi Yuan, Jin Wang
Summary: In this research, monodispersed Mg-doped ZnO nanoparticles were synthesized through low temperature hydrothermal method, showing improved optical band gap and photoluminescence performance with increasing Mg content. The visible emission band consists of green, yellow, and red emission bands associated with different defect states, which can be explained by the analysis of Mg content- and temperature-dependent photoluminescence spectra.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Ala Hamd Hssain, Niyazi Bulut, Tankut Ates, Suleyman Koytepe, Ali Kurucay, Hanifi Kebiroglu, Omer Kaygili
Summary: This study presents an extensive experimental and theoretical analysis of Mg-doped hydroxyapatite samples with additional Sm doping at varying amounts. The results show that the bandgap energy decreases and the linear attenuation coefficient increases with increasing Sm doping. The XRD and FTIR analysis reveals the phase composition and lattice parameters of the samples. The samples exhibit good thermal stability, but cell viability is affected by the presence of Sm.
CHEMICAL PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
J. C. Sancho-Garcia, E. Bremond, G. Ricci, A. J. Perez-Jimenez, Y. Olivier, C. Adamo
Summary: In this study, the energy difference between the lowest singlet and triplet excited states of a set of azaphenalene compounds, which violate Hund's rule and show an inversion of state order, is calculated using a family of double-hybrid density functionals. The results demonstrate that these double-hybrid density functional models, with the approximate inclusion of double excitations, can accurately predict the energy order and energy difference of the excited states.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Eric Bremond, Vincent Tognetti, Henry Chermette, Juan Carlos Sancho-Garcia, Laurent Joubert, Carlo Adamo
Summary: This study investigates the relationships between electron-density and electronic-energy errors produced by modern exchange-correlation density-functional approximations, and explores the strengths and weaknesses of the most recent and efficient density-functional approximations through comparison of their performance in terms of density- and energy-based errors on a large selection of molecular systems.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
Eric Bremond, Marika Savarese, Nadia Rega, Ilaria Ciofini, Carlo Adamo
Summary: By using different density functional approximations, we reconstructed the free energy profiles along reaction pathways and compared the computed barrier heights of proton transfer reactions using two different methods. The results show that the choice of density functional has a significant impact on the computed results, with local density functionals often underestimating the barrier heights.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
E. Bremond, A. J. Perez-Jimenez, C. Adamo, J. C. Sancho-Garcia
Summary: In this study, the relative energy between different structures of C4k+2 (k = 4-7) rings prompted by the synthesis of cyclo[18]carbon compounds was calculated. Reference results obtained through Quantum Monte-Carlo (QMC) approach were used as benchmarks to compare the performance of various wavefunction methods and density functionals. The use of range-separated double-hybrid functionals showed high accuracy and competitive results compared to the reference approach, DLPNO-CCSD(T), at a more reasonable computational cost.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Eric Bremond, Hanwei Li, Angel Jose Perez-Jimenez, Juan Carlos Sancho-Garcia, Carlo Adamo
Summary: In this study, we evaluate the performance of 18 double-hybrid density functionals in modeling the thermochemical and kinetic properties of 449 organic chemistry reactions. We find that most of the double-hybrid functionals provide statistically robust results in modeling barrier height and reaction energies to chemical accuracy. Nonempirical and minimally parameterized double-hybrid functionals show balanced accuracy in modeling both properties, while parameterized approaches tend to be biased towards only one of the properties.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Eric Bremond, Hanwei Li, Juan Carlos Sancho-Garcia, Carlo Adamo
Summary: This study explores a method for accurately evaluating weak noncovalent interactions in large molecular systems. The PBE-QIDH/DH-SVPD protocol shows high accuracy and computational speed for large systems, but has limitations when dealing with complex molecular structures and limited reference data.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Review
Chemistry, Physical
J. C. Sancho-Garcia, E. Bremond, A. J. Perez-Jimenez, I Ciofini, C. Adamo
Summary: The development of approximations for electronic structure calculations is crucial in theoretical and computational chemistry. We have developed a set of non-empirical density functional expressions that are accurate, widely applicable, and can compete with wavefunction methods. These methods can be applied to study key properties such as chemical structure, reactivity, bonding, and also photochemistry and photophysics.
ELECTRONIC STRUCTURE
(2022)
Article
Chemistry, Physical
M. E. Sandoval-Salinas, E. Bremond, A. J. Perez-Jimenez, C. Adamo, J. C. Sancho-Garcia
Summary: A family of non-empirical double-hybrid density functionals based on Perdew-Burke-Ernzerhof (PBE) exchange and correlation functionals is utilized to calculate the excitation energies of linear and cyclic acenes. The calculated energies for different states are compared with experimental results and other double-hybrid expressions. The study demonstrates that these non-empirical functionals outperform hybrid functionals and provide competitive results.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Silvia Di Grande, Ilaria Ciofini, Carlo Adamo, Marco Pagliai, Gianni Cardini
Summary: This study focuses on modeling the electronic absorption spectrum of a fluorescent probe using a combined classical-quantum chemical approach. The results emphasize the importance of conformational sampling and the influence of different exchange and correlation functionals on the spectral profile. Hybrid functionals enable accurate reproduction of the observed absorption maxima.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Physical
Maciej Spiegel, Carlo Adamo
Summary: Photosensitizers with the Ru(II)-polypyridyl complex structure have shown potential as photodynamic therapy agents for treating neoplasms, but their poor solubility has been a challenge. This study investigates the use of a polyamine macrocycle ring as a solution to improve solubility. The results suggest that protonation of amine groups enhances reactivity, but complexation weakens the desired photoactivity.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Lorenzo Briccolani-Bandini, Eric Bremond, Marco Pagliai, Gianni Cardini, Ilaria Ciofini, Carlo Adamo
Summary: In this study, the double proton transfer (PT) reaction in the complex molecule [2,2'-bipyridyl]-3-3'-diol was explored, revealing the coupling of proton movements with significant rearrangement of the electronic structure. The reaction could occur simultaneously (concerted) or sequentially (stepwise), with the characteristics of the stepwise PT depending on the chosen exchange-correlation functionals. The potential energy surface (PES) and free-energy surface (FES) were analyzed using density functional theory, showing variations in the stepwise mechanism and the presence of stable intermediates and transition states.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Chemistry, Physical
Maryam Mansoori Kermani, Hanwei Li, Alistar Ottochian, Orlando Crescenzi, Benjamin G. Janesko, Giovanni Scalmani, Michael J. Frisch, Ilaria Ciofini, Carlo Adamo, Donald G. Truhlar
Summary: Theoretical characterization of reactions of complex molecules requires accurate determination of the relative energies of intermediates and transition states. In this study, the DLPNO-CCSD(T) method was employed to provide benchmark values for Diels-Alder transition states leading to strained pentacyclic adducts. Various wave function and density functional methods were compared for their prediction of absolute and relative barrier heights. The results show that only a few density functionals can satisfactorily predict absolute barrier heights, while relative barrier heights are more accurate. The findings of this study can guide the selection of density functionals for future studies on crowded, strained transition states of large molecules.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Michele Turelli, Ilaria Ciofini, Qinfan Wang, Alistar Ottochian, Frederic Labat, Carlo Adamo
Summary: Organic luminophores with luminescence enhancement in solid state have great potential for the development of functional materials. However, the understanding of the molecular interactions responsible for the macroscopic response is limited. Theoretical frameworks that provide mechanistic explanations and quantitative predictions are important for the understanding of solid-state luminescence enhancement.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Andrew M. Teale, Trygve Helgaker, Andreas Savin, Carlo Adamo, Balint Aradi, Alexei Arbuznikov, Paul W. Ayers, Evert Jan Baerends, Vincenzo Barone, Patrizia Calaminici, Eric Cances, Emily A. Carter, Pratim Kumar Chattaraj, Henry Chermette, Ilaria Ciofini, T. Daniel Crawford, Frank De Proft, John F. Dobson, Claudia Draxl, Thomas Frauenheim, Emmanuel Fromager, Patricio Fuentealba, Laura Gagliardi, Giulia Galli, Jiali Gao, Paul Geerlings, Nikitas Gidopoulos, Peter M. W. Gill, Paola Gori-Giorgi, Andreas Gorling, Tim Gould, Stefan Grimme, Oleg Gritsenko, Hans Jorgen Aagaard Jensen, Erin R. Johnson, Robert O. Jones, Martin Kaupp, Andreas M. Koster, Leeor Kronik, Anna Krylov, Simen Kvaal, Andre Laestadius, Mel Levy, Mathieu Lewin, Shubin Liu, Pierre-Francois Loos, Neepa T. Maitra, Frank Neese, John P. Perdew, Katarzyna Pernal, Pascal Pernot, Piotr Piecuch, Elisa Rebolini, Lucia Reining, Pina Romaniello, Adrienn Ruzsinszky, Dennis R. Salahub, Matthias Scheffler, Peter Schwerdtfeger, Viktor N. Staroverov, Jianwei Sun, Erik Tellgren, David J. Tozer, Samuel B. Trickey, Carsten A. Ullrich, Alberto Vela, Giovanni Vignale, Tomasz A. Wesolowski, Xin Xu, Weitao Yang
Summary: This paper provides an informal review and discussion on the history, present status, and future of density-functional theory (DFT) by 70 workers in the field. The format of a roundtable discussion allowed participants to express their views through 302 individual contributions to a preset list of 26 questions. Supported by a bibliography of 777 entries, the paper offers a comprehensive snapshot of DFT in 2022.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Cosimo Micheletti, Qinfan Wang, Francesco Ventura, Michele Turelli, Ilaria Ciofini, Carlo Adamo, Andrea Pucci
Summary: This study explores the preparation of red-emitting luminescent solar concentrators using an aggregation-induced enhanced emission fluorophore and investigates the behavior of the fluorophore in different environments. The results show that by suppressing the aggregation of the fluorophore, the luminescence performance and quantum yield can be improved, leading to enhanced performance of the luminescent solar concentrators.
