Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods ...Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods generally involve the exploration of the potential energy surfaces of materials through various structure sampling techniques and optimization algorithms in conjunction with quantum mechanical calculations. By taking advantage of the general feature of materials potential energy surface and swarm-intelligence-based global optimization algorithms, we have developed the CALYPSO method for structure prediction, which has been widely used in fields as diverse as computational physics, chemistry, and materials science. In this review, we provide the basic theory of the CALYPSO method, placing particular emphasis on the principles of its various structure dealing methods. We also survey the current challenges faced by structure prediction methods and include an outlook on the future developments of CALYPSO in the conclusions.展开更多
In recent years, structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D) materials...In recent years, structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D) materials. Here we highlight some most recent research progress on the prediction of novel 2D structures, involving elements, metal-free and metal-containing compounds using CALYPSO package. Particular emphasis will be given to those 2D materials that exhibit unique electronic and magnetic properties with great potentials for applications in novel electronics, optoelectronics,magnetronics, spintronics, and photovoltaics. Finally, we also comment on the challenges and perspectives for future discovery of multi-functional 2D materials.展开更多
Cluster science as a bridge linking atomic molecular physics and condensed matter inspired the nanomaterials development in the past decades, ranging from the single-atom catalysis to ligand-protected noble metal clus...Cluster science as a bridge linking atomic molecular physics and condensed matter inspired the nanomaterials development in the past decades, ranging from the single-atom catalysis to ligand-protected noble metal clusters. The corresponding studies not only have been restricted to the search for the geometrical structures of clusters, but also have promoted the development of cluster-assembled materials as the building blocks. The CALYPSO cluster prediction method combined with other computational techniques have significantly stimulated the development of the cluster-based nanomaterials. In this review, we will summarize some good cases of cluster structure by CALYPSO method, which have also been successfully identified by the photoelectron spectra experiments. Beginning with the alkali-metal clusters, which serve as benchmarks, a series of studies are performed on the size-dependent elemental clusters which possess relatively high stability and interesting chemical physical properties. Special attentions are paid to the boron-based clusters because of their promising applications. The NbSi12 and BeB16 clusters, for example, are two classic representatives of the silicon-and boron-based clusters, which can be viewed as building blocks of nanotubes and borophene. This review offers a detailed description of the structural evolutions and electronic properties of medium-sized pure and doped clusters, which will advance fundamental knowledge of cluster-based nanomaterials and provide valuable information for further theoretical and experimental studies.展开更多
Hydrogen-rich compounds are promising candidates for high-Tc or even room-temperature superconductors. The search for high-Tc hydrides poses a major experimental challenge because there are many known hydrides and eve...Hydrogen-rich compounds are promising candidates for high-Tc or even room-temperature superconductors. The search for high-Tc hydrides poses a major experimental challenge because there are many known hydrides and even more unknown hydrides with unusual stoichiometries under high pressure. The combination of crystal structure prediction and first-principles calculations has played an important role in the search for high-Tc hydrides, especially in guiding experimental synthesis. Crystal structure AnaLYsis by Particle Swarm Optimization(CALYPSO) is one of the most efficient methods for predicting stable or metastable structures from the chemical composition alone. This review summarizes the superconducting hydrides predicted using CALYPSO. We focus on two breakthroughs toward room-temperature superconductors initiated by CALYPSO: the prediction of high-Tc superconductivity in compressed hydrogen sulfide and lanthanum hydrides, both of which have been confirmed experimentally and have set new record Tc values. We also address the challenges and outlook in this field.展开更多
The study of superhard materials plays a critical role in modern industrial applications due to their widespread applications as cutting tools, abrasives, exploitation drills, and coatings. The search for new superhar...The study of superhard materials plays a critical role in modern industrial applications due to their widespread applications as cutting tools, abrasives, exploitation drills, and coatings. The search for new superhard materials with superior performance remains a hot topic and is mainly considered as two classes of materials:(i) the light-element compounds in the B-C-N-O(-Si) system with strong and short covalent bonds, and(ii) the transition-element light-element compounds with strong covalent bonds frameworks and high valence electron density. In this paper, we review the recent achievements in the prediction of superhard materials mostly using the advanced CALYPSO methodology. A number of novel, superhard crystals of light-element compounds and transition-metal borides, carbides, and nitrides have been theoretically identified and some of them account well for the experimentally mysterious phases. To design superhard materials via CALYPSO methodology is independent of any known structural and experimental data, resulting in many remarkable structures accelerating the development of new superhard materials.展开更多
Divalent metal clusters have received great attention due to the interesting size-induced nonmetal-to-metal transition and fascinating properties dependent on cluster size,shape,and doping.In this work,the combination...Divalent metal clusters have received great attention due to the interesting size-induced nonmetal-to-metal transition and fascinating properties dependent on cluster size,shape,and doping.In this work,the combination of the CALYPSO code and density functional theory(DFT)optimization is employed to explore the structural properties of neutral and anionic Mg_(n+1) and SrMgn(n=2-12)clusters.The results exhibit that as the atomic number of Mg increases,Sr atoms are more likely to replace Mg atoms located in the skeleton convex cap.By analyzing the binding energy,second-order energy difference and the charge transfer,it can be found the SrMg9 cluster with tower framework presents outstanding stability in a studied size range.Further,bonding characteristic analysis reveals that the stability of SrMg9 can be improved due to the strong s-p interaction among the atomic orbitals of Sr and Mg atoms.展开更多
Electrides are unique ionic compounds that electrons serve as the anions. Many electrides with fascinating physical and chemical properties have been discovered at ambient condition. Under pressure, electrides are als...Electrides are unique ionic compounds that electrons serve as the anions. Many electrides with fascinating physical and chemical properties have been discovered at ambient condition. Under pressure, electrides are also revealed to be ubiquitous crystal morphology, enriching the geometrical topologies and electronic properties of electrides. In this Review,we overview the formation mechanism of high-pressure electrides(HPEs) and outline a scheme for exploring new HPEs from pre-design, CALYPSO assisted structural searches, indicators for electrides, to experimental synthesis. Moreover, the evolution of electronic dimensionality under compression is also discussed to better understand the dimensional distribution of anionic electrons in HPEs.展开更多
The dimensionality of structures allows materials to be classified into zero-, one-, two-, and threedimensional systems. Two-dimensional (2D) systems have attracted a great deal of attention andtypically include surfa...The dimensionality of structures allows materials to be classified into zero-, one-, two-, and threedimensional systems. Two-dimensional (2D) systems have attracted a great deal of attention andtypically include surfaces, interfaces, and layered materials. Due to their varied properties, 2D systemshold promise for applications such as electronics, optoelectronics, magnetronics, and valleytronics.The design of 2D systems is an area of intensive research because of the rapid development of abinitio structure-searching methods. In this paper, we highlight recent research progress on acceleratingthe design of 2D systems using the CALYPSO methodology. Challenges and perspectives for futuredevelopments in 2D structure prediction methods are also presented.展开更多
Bimetallic clusters have aroused tremendous interest because the property changes like structure,size,and composition have occurred.Herein,a structural search of the global minimum for anionic LiMg_(n)^(-)(n=2-11) clu...Bimetallic clusters have aroused tremendous interest because the property changes like structure,size,and composition have occurred.Herein,a structural search of the global minimum for anionic LiMg_(n)^(-)(n=2-11) clusters is performed using an efficient crystal structure analysis by particle swarm optimization(CALYPSO) structural searching program with subsequent density functional theory(DFT) calculations.A great variety of low energetic isomers are converged,and the most stable ones are confirmed by comparing their total energy of each size.It is found that the LiMg_(n)^(-)clusters are structurally consistent with corresponding Mg clusters anions except for LiMg_(5)^(-)and LiMg_(7)^(-).In all the doped clusters,the Li atom prefers to occupy the convex position.Simulated photoelectron spectra(PES),Infrared(IR),and Raman spectra of LiMg_(n)^(-)could be used as an essential evidence for identifying cluster structures experimentally in the future.Stability study reveals that a tower-like structure of LiMg_(9)^(-)has prominent stability and can be identified as a magic number cluster.The reason might be that there are both closed-shell 1S^(2)1P^(6)1D^(10)2S^(2) electronic configurations and stronger Li-Mg bonds caused by sp hybridization in the LiMg_(9)^(-)cluster.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11534003 and 11604117)the National Key Research and Development Program of China(Grant No.2016YFB0201201)+1 种基金the Program for JLU Science and Technology Innovative Research Team(JLUSTIRT)of Chinathe Science Challenge Project of China(Grant No.TZ2016001)
文摘Structure prediction methods have been widely used as a state-of-the-art tool for structure searches and materials discovery, leading to many theory-driven breakthroughs on discoveries of new materials. These methods generally involve the exploration of the potential energy surfaces of materials through various structure sampling techniques and optimization algorithms in conjunction with quantum mechanical calculations. By taking advantage of the general feature of materials potential energy surface and swarm-intelligence-based global optimization algorithms, we have developed the CALYPSO method for structure prediction, which has been widely used in fields as diverse as computational physics, chemistry, and materials science. In this review, we provide the basic theory of the CALYPSO method, placing particular emphasis on the principles of its various structure dealing methods. We also survey the current challenges faced by structure prediction methods and include an outlook on the future developments of CALYPSO in the conclusions.
基金support by Australian Research Council under Discovery Project (Grant No. DP170103598)the Pawsey Supercomputing Centre through the National Computational Merit Allocation Scheme supported by the Australian Government and the Government of Western Australia
文摘In recent years, structure design and predictions based on global optimization approach as implemented in CALYPSO software have gained great success in accelerating the discovery of novel two-dimensional(2D) materials. Here we highlight some most recent research progress on the prediction of novel 2D structures, involving elements, metal-free and metal-containing compounds using CALYPSO package. Particular emphasis will be given to those 2D materials that exhibit unique electronic and magnetic properties with great potentials for applications in novel electronics, optoelectronics,magnetronics, spintronics, and photovoltaics. Finally, we also comment on the challenges and perspectives for future discovery of multi-functional 2D materials.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1804121 and 11304167)
文摘Cluster science as a bridge linking atomic molecular physics and condensed matter inspired the nanomaterials development in the past decades, ranging from the single-atom catalysis to ligand-protected noble metal clusters. The corresponding studies not only have been restricted to the search for the geometrical structures of clusters, but also have promoted the development of cluster-assembled materials as the building blocks. The CALYPSO cluster prediction method combined with other computational techniques have significantly stimulated the development of the cluster-based nanomaterials. In this review, we will summarize some good cases of cluster structure by CALYPSO method, which have also been successfully identified by the photoelectron spectra experiments. Beginning with the alkali-metal clusters, which serve as benchmarks, a series of studies are performed on the size-dependent elemental clusters which possess relatively high stability and interesting chemical physical properties. Special attentions are paid to the boron-based clusters because of their promising applications. The NbSi12 and BeB16 clusters, for example, are two classic representatives of the silicon-and boron-based clusters, which can be viewed as building blocks of nanotubes and borophene. This review offers a detailed description of the structural evolutions and electronic properties of medium-sized pure and doped clusters, which will advance fundamental knowledge of cluster-based nanomaterials and provide valuable information for further theoretical and experimental studies.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11804128 and 11722433)the Qing Lan Project of Jiangsu Province,Chinathe Six Talent Peaks Project of Jiangsu Province,China
文摘Hydrogen-rich compounds are promising candidates for high-Tc or even room-temperature superconductors. The search for high-Tc hydrides poses a major experimental challenge because there are many known hydrides and even more unknown hydrides with unusual stoichiometries under high pressure. The combination of crystal structure prediction and first-principles calculations has played an important role in the search for high-Tc hydrides, especially in guiding experimental synthesis. Crystal structure AnaLYsis by Particle Swarm Optimization(CALYPSO) is one of the most efficient methods for predicting stable or metastable structures from the chemical composition alone. This review summarizes the superconducting hydrides predicted using CALYPSO. We focus on two breakthroughs toward room-temperature superconductors initiated by CALYPSO: the prediction of high-Tc superconductivity in compressed hydrogen sulfide and lanthanum hydrides, both of which have been confirmed experimentally and have set new record Tc values. We also address the challenges and outlook in this field.
基金Project supported by the National Key Research and Development Program of China(Grant No.2018YFA0703400)the National Natural Science Foundation of China(Grant Nos.51722209,51572235,and 51672238)+2 种基金the 100 Talents Plan of Hebei Province of China(Grant No.E2016100013)the NSF for Distinguished Young Scholars of Hebei Province of China(Grant No.E2018203349)the Key Research and Development Program of Hebei Province of China(Grant No.17211110D)
文摘The study of superhard materials plays a critical role in modern industrial applications due to their widespread applications as cutting tools, abrasives, exploitation drills, and coatings. The search for new superhard materials with superior performance remains a hot topic and is mainly considered as two classes of materials:(i) the light-element compounds in the B-C-N-O(-Si) system with strong and short covalent bonds, and(ii) the transition-element light-element compounds with strong covalent bonds frameworks and high valence electron density. In this paper, we review the recent achievements in the prediction of superhard materials mostly using the advanced CALYPSO methodology. A number of novel, superhard crystals of light-element compounds and transition-metal borides, carbides, and nitrides have been theoretically identified and some of them account well for the experimentally mysterious phases. To design superhard materials via CALYPSO methodology is independent of any known structural and experimental data, resulting in many remarkable structures accelerating the development of new superhard materials.
基金the National Natural Science Foundation of China(Grant No.11404008)the Artificial Intelligence Key Laboratory of Sichuan Province,China(Grant No.2018RYJ07)+2 种基金the Innovation Fund of Postgraduate Sichuan University of Science&Engineering,China(Grant Nos.y202007 and y2021008)the Innovation and Entrepreneurship Training Program of Sichuan Province,China(Grant Nos.S202010622080 and S202010622082)the Innovation and Entrepreneurship Training Program of Sichuan University of Science&Engineering,China(Grant No.cx2019005)。
文摘Divalent metal clusters have received great attention due to the interesting size-induced nonmetal-to-metal transition and fascinating properties dependent on cluster size,shape,and doping.In this work,the combination of the CALYPSO code and density functional theory(DFT)optimization is employed to explore the structural properties of neutral and anionic Mg_(n+1) and SrMgn(n=2-12)clusters.The results exhibit that as the atomic number of Mg increases,Sr atoms are more likely to replace Mg atoms located in the skeleton convex cap.By analyzing the binding energy,second-order energy difference and the charge transfer,it can be found the SrMg9 cluster with tower framework presents outstanding stability in a studied size range.Further,bonding characteristic analysis reveals that the stability of SrMg9 can be improved due to the strong s-p interaction among the atomic orbitals of Sr and Mg atoms.
文摘Electrides are unique ionic compounds that electrons serve as the anions. Many electrides with fascinating physical and chemical properties have been discovered at ambient condition. Under pressure, electrides are also revealed to be ubiquitous crystal morphology, enriching the geometrical topologies and electronic properties of electrides. In this Review,we overview the formation mechanism of high-pressure electrides(HPEs) and outline a scheme for exploring new HPEs from pre-design, CALYPSO assisted structural searches, indicators for electrides, to experimental synthesis. Moreover, the evolution of electronic dimensionality under compression is also discussed to better understand the dimensional distribution of anionic electrons in HPEs.
基金supported by the National Natural Science Foundation of China(Grant Nos.12034009,91961204,11874175,11874176,11974134,and 12074138)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB33000000)+2 种基金the Fundamental Research Funds for the Central Universities(Jilin University,JLU)the Program for JLU Science and Technology Innovative Research Team(JLUSTIRT)Jilin Province Outstanding Young Talents Project No.20190103040JH.
文摘The dimensionality of structures allows materials to be classified into zero-, one-, two-, and threedimensional systems. Two-dimensional (2D) systems have attracted a great deal of attention andtypically include surfaces, interfaces, and layered materials. Due to their varied properties, 2D systemshold promise for applications such as electronics, optoelectronics, magnetronics, and valleytronics.The design of 2D systems is an area of intensive research because of the rapid development of abinitio structure-searching methods. In this paper, we highlight recent research progress on acceleratingthe design of 2D systems using the CALYPSO methodology. Challenges and perspectives for futuredevelopments in 2D structure prediction methods are also presented.
基金Project supported by the National Natural Science Foundation of China(Grant No.11404008)the Innovation Training Program for College Students of Shanxi Province of China(Grant No.S201910721061)the Innovation Training Program for College Students of Baoji University of Arts and Sciences(Grant No.20191XJ087)。
文摘Bimetallic clusters have aroused tremendous interest because the property changes like structure,size,and composition have occurred.Herein,a structural search of the global minimum for anionic LiMg_(n)^(-)(n=2-11) clusters is performed using an efficient crystal structure analysis by particle swarm optimization(CALYPSO) structural searching program with subsequent density functional theory(DFT) calculations.A great variety of low energetic isomers are converged,and the most stable ones are confirmed by comparing their total energy of each size.It is found that the LiMg_(n)^(-)clusters are structurally consistent with corresponding Mg clusters anions except for LiMg_(5)^(-)and LiMg_(7)^(-).In all the doped clusters,the Li atom prefers to occupy the convex position.Simulated photoelectron spectra(PES),Infrared(IR),and Raman spectra of LiMg_(n)^(-)could be used as an essential evidence for identifying cluster structures experimentally in the future.Stability study reveals that a tower-like structure of LiMg_(9)^(-)has prominent stability and can be identified as a magic number cluster.The reason might be that there are both closed-shell 1S^(2)1P^(6)1D^(10)2S^(2) electronic configurations and stronger Li-Mg bonds caused by sp hybridization in the LiMg_(9)^(-)cluster.
