The exploratory synthesis and structural characterization of twodimensional(2D)honeycomb structured Ru-based compounds are key focuses in inorganic materials research,due to the various exotic electronic states arisin...The exploratory synthesis and structural characterization of twodimensional(2D)honeycomb structured Ru-based compounds are key focuses in inorganic materials research,due to the various exotic electronic states arising from the interplay of electron correlations and spinorbit coupling.Among these compounds,α-RuCl_(3) and RuBr_(3) are considered as the most promising candidates for quantum spin liquid(QSL)materials[1–3].As a homolog,α-RuI3 has attracted significant interest,but it still remains relatively unexplored.Recently,it was synthesized by high-temperature and high-pressure solid-state reaction,but reported to be different crystal structures by independent groups.Ni et al.and Nawa et al.considerα-RuI3 to be R-3(3R)and P-31c(2H)space group,respectively[4,5].Both structures have typical 2D characteristics,in which the edge-sharing RuI6 octahedra form honeycomb layers stacked along the c-axis.The primary difference lies in that the honeycomb layers stack in ABCABC mode in the 3R phase,while in ABAB mode in the 2H phase(Fig.S1).Yang et al.discussed the stability of 3R and 2H polymorphs in terms of the total energies and dynamics,finding both structures are stable.However,the total energy of the 2H phase is slightly higher,2.58 meV than that of the 3R analog[6].When it comes to the conductivity behaviour,α-RuCl3 andα-RuBr_(3) are semiconductors as normally observed in QSL materials.In contrast,α-RuI_(3) exhibits metallic response.In 2D materials,the band structure may be drastically modified by altering the stacking order[7].Hence,determining the crystal structure ofα-RuI_(3) is urgently required,which is a key step in comprehensive and in-depth analysis of its physical properties.展开更多
基金supported by the National Natural Science Foundation of China(No.22090041)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(No.2017ZT07C069)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(No.2022B1515120014)the Natural Science Foundation of Zhejiang Province(No.LQ21A040010).
文摘The exploratory synthesis and structural characterization of twodimensional(2D)honeycomb structured Ru-based compounds are key focuses in inorganic materials research,due to the various exotic electronic states arising from the interplay of electron correlations and spinorbit coupling.Among these compounds,α-RuCl_(3) and RuBr_(3) are considered as the most promising candidates for quantum spin liquid(QSL)materials[1–3].As a homolog,α-RuI3 has attracted significant interest,but it still remains relatively unexplored.Recently,it was synthesized by high-temperature and high-pressure solid-state reaction,but reported to be different crystal structures by independent groups.Ni et al.and Nawa et al.considerα-RuI3 to be R-3(3R)and P-31c(2H)space group,respectively[4,5].Both structures have typical 2D characteristics,in which the edge-sharing RuI6 octahedra form honeycomb layers stacked along the c-axis.The primary difference lies in that the honeycomb layers stack in ABCABC mode in the 3R phase,while in ABAB mode in the 2H phase(Fig.S1).Yang et al.discussed the stability of 3R and 2H polymorphs in terms of the total energies and dynamics,finding both structures are stable.However,the total energy of the 2H phase is slightly higher,2.58 meV than that of the 3R analog[6].When it comes to the conductivity behaviour,α-RuCl3 andα-RuBr_(3) are semiconductors as normally observed in QSL materials.In contrast,α-RuI_(3) exhibits metallic response.In 2D materials,the band structure may be drastically modified by altering the stacking order[7].Hence,determining the crystal structure ofα-RuI_(3) is urgently required,which is a key step in comprehensive and in-depth analysis of its physical properties.
