Despite the widespread use of birefringence crystals in optical instruments,the birefringence of commercially available crystals is generally limited(Δn<0.3),making them less suitable for demanding optical require...Despite the widespread use of birefringence crystals in optical instruments,the birefringence of commercially available crystals is generally limited(Δn<0.3),making them less suitable for demanding optical requirements.In this work,three novel birefringent crystals,namely(C_(2)N_(5)H_(8))(H_(2)C_(3)N_(3)O_(3))·H_(2)O(1),(C_(2)N_(5)H_(8))_(3)(H_(2)C_(3)N_(3)S_(3))(HC_(3)N_(3)S_(3))·H_(2)O(2),and(C_(2)N_(5)H_(8))(H_(2)C_(3)N_(3)S_(3))·H_(2)O(3),were successfully synthesized via a two-step strategy.In their anionic structures,a displaced parallel arrangement is observed among three crystals,combined with a partially distinct arbitrary intersecting arrangement.Further research findings indicate that sulfur(S)substitution(from 1 to 2)and the optimized arrangement of functional groups(from 2 to 3)lead to a significant enhancement in the birefringence.The experimental birefringence values at 550 nm increased from 0.259(1)to 0.347(2),reaching 0.403(3).Remarkably,the birefringence performance of compound 3 ranks third among all reported[C_(3)N_(3)S_(3)]-based materials.Theoretical calculations reveal that its high birefringence is primarily attributed to S-substitution and the optimized arrangement of functional groups.This work provides critical guidance for further exploration of the impact of structure on birefringence performance and opens up new research directions for designing high-performance optical materials.展开更多
Emerging machine learning interatomic potentials(MLIPs)offer a promising solution for large-scale accurate material simulations,but stringent tests related to the description of vibrational dynamics in molecular cryst...Emerging machine learning interatomic potentials(MLIPs)offer a promising solution for large-scale accurate material simulations,but stringent tests related to the description of vibrational dynamics in molecular crystals remain scarce.Here,we develop a general MLIP by leveraging the graph neural network-based MACE architecture and active-learning strategies to accurately capture vibrational dynamics across a range of polyacene-based molecular crystals,namely naphthalene,anthracene,tetracene and pentacene.Through careful error propagation,we show that these potentials are accurate and enable the study of anharmonic vibrational features,vibrational lifetimes,and vibrational coupling.In particular,we investigate large-scale host-vip systems based on these molecular crystals,showing the capacity of molecular-dynamics-based techniques to explain and quantify vibrational coupling between host and vip nuclear motion.Our results establish a framework for understanding vibrational signatures in large-scale complex molecular systems and thus represent an important step for engineering vibrational interactions in molecular environments.展开更多
基金supported by the National Natural Science Foundation of China(22193042,22435005,21921001,22125110,22122507,U21A2069,22201110,and 21833010)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(ZDBS-LY-SLH024)+4 种基金the Fujian Provincial Natural Science Foundation(2021J01523 and 2020J01112)the Youth Innovation Promotion of CAS(2019301,Y202069,and 2020307)the Young Talent Supporting Project of Fujian Association of Science and Technology(2021000008)the National Key Research and Development Program of China(2019YFA0210402)the Jiangxi Provincial Natural Science Foundation(20232BAB213023 and 20243BCE51156).
文摘Despite the widespread use of birefringence crystals in optical instruments,the birefringence of commercially available crystals is generally limited(Δn<0.3),making them less suitable for demanding optical requirements.In this work,three novel birefringent crystals,namely(C_(2)N_(5)H_(8))(H_(2)C_(3)N_(3)O_(3))·H_(2)O(1),(C_(2)N_(5)H_(8))_(3)(H_(2)C_(3)N_(3)S_(3))(HC_(3)N_(3)S_(3))·H_(2)O(2),and(C_(2)N_(5)H_(8))(H_(2)C_(3)N_(3)S_(3))·H_(2)O(3),were successfully synthesized via a two-step strategy.In their anionic structures,a displaced parallel arrangement is observed among three crystals,combined with a partially distinct arbitrary intersecting arrangement.Further research findings indicate that sulfur(S)substitution(from 1 to 2)and the optimized arrangement of functional groups(from 2 to 3)lead to a significant enhancement in the birefringence.The experimental birefringence values at 550 nm increased from 0.259(1)to 0.347(2),reaching 0.403(3).Remarkably,the birefringence performance of compound 3 ranks third among all reported[C_(3)N_(3)S_(3)]-based materials.Theoretical calculations reveal that its high birefringence is primarily attributed to S-substitution and the optimized arrangement of functional groups.This work provides critical guidance for further exploration of the impact of structure on birefringence performance and opens up new research directions for designing high-performance optical materials.
基金support from the Cluster of Excellence“CUI:Advanced Imaging of Matter”—EXC 2056—project ID 390715994BiGmax,the Max Planck Society Research Network on Big-Data-Driven Materials-Science and the Max Planck-New York City Center for Non-Equilibrium Quantum Phenomena.The Flatiron Institute is a division of the Simons Foundation+1 种基金We also acknowledge support from the European Research Council MSCA-ITN TIMES under grant agreement 101118915S.S.and P.L.acknowledge support from the UFAST International Max Planck Research School.
文摘Emerging machine learning interatomic potentials(MLIPs)offer a promising solution for large-scale accurate material simulations,but stringent tests related to the description of vibrational dynamics in molecular crystals remain scarce.Here,we develop a general MLIP by leveraging the graph neural network-based MACE architecture and active-learning strategies to accurately capture vibrational dynamics across a range of polyacene-based molecular crystals,namely naphthalene,anthracene,tetracene and pentacene.Through careful error propagation,we show that these potentials are accurate and enable the study of anharmonic vibrational features,vibrational lifetimes,and vibrational coupling.In particular,we investigate large-scale host-vip systems based on these molecular crystals,showing the capacity of molecular-dynamics-based techniques to explain and quantify vibrational coupling between host and vip nuclear motion.Our results establish a framework for understanding vibrational signatures in large-scale complex molecular systems and thus represent an important step for engineering vibrational interactions in molecular environments.
