The formation of stable neutral helium-and neon-containing compounds under ambient conditions remains a signifi-cant challenge in chemistry.Here we de-velop a novel strategy for the synthesis of helium-and neon-contai...The formation of stable neutral helium-and neon-containing compounds under ambient conditions remains a signifi-cant challenge in chemistry.Here we de-velop a novel strategy for the synthesis of helium-and neon-containing complex-es with a helium or neon atom encapsu-lated by two molecules with large elec-tric dipole moments.Using high-level ab initio calculations,we find that linear compounds,such as LiF-He-CuF,HCN-He-CuF,NaF-Ne-CuF,LiF-Ne-AuF and NaF-Ne-AuF,are stable,and the strong interac-tions resulting from the head-to-tail alignment of large electric dipoles have significantly en-hanced the He/Ne-metal binding when compared with those predicted for the He-CuF and Ne-AuF complexes.A viable experimental approach to synthesize these compounds is also out-lined,offering a potential route to stable neutral compounds containing both helium and neon under ambient conditions.展开更多
A Bench top Quadrupole Mass Spectrometer System for Accurate Analysis of Trace Noble Gas was introduced in this paper. The inlet system was a especially designed one. And a capacitance pressure gauge with its linearit...A Bench top Quadrupole Mass Spectrometer System for Accurate Analysis of Trace Noble Gas was introduced in this paper. The inlet system was a especially designed one. And a capacitance pressure gauge with its linearity less than 0.01% was used to measure the fixed volume sample ratio. By using the calibration gas with the uncertainty of which less than 0.1% ,isotope condensed diluent could be quantified online. The procedure is done by alternate online mixture gas measurement of diluent gas, calibration gas to quantify the diluent gas, and diluent gas, sample gas to quantify the sample gas. The precision of six inlet from the same sample is +_0.13%0; The precision of six getting sample from the same source is less than ±0.5%. Self test was done by testing the mixture gas got with weighing method, in which consists Kr and Xe of 30 mg/kg. The system uncertainty tested to be below ±1%.展开更多
A new approach to the quatitative analysis of Kr and Xe by isotope dilution mass spectrometry (IDMS) has been developed using inductively coupled plasma mass spectrometry (ICP-MS). The typical relative standard uncert...A new approach to the quatitative analysis of Kr and Xe by isotope dilution mass spectrometry (IDMS) has been developed using inductively coupled plasma mass spectrometry (ICP-MS). The typical relative standard uncertainties of Kr and Xe IDMS are 1%.展开更多
Metal superhydride compounds(MSHCs)have attracted much attention in the fields of high-pressure physics due to the superconductivity properties deriving from the metallic-hydrogen-like characteristics and relatively m...Metal superhydride compounds(MSHCs)have attracted much attention in the fields of high-pressure physics due to the superconductivity properties deriving from the metallic-hydrogen-like characteristics and relatively mild synthesis conditions.However,their energetic performance and related potential applications are still open issues till now.In this study,CaH_(6)and NbH_(3),which exhibit evidently differences in their geometric and electronic structures,were chosen as examples of MSHCs to investigate their energetic performance.The structure,bonding features and energetic performance of CaH_(6)and NbH_(3)were predicted based on first-principles calculations.Our results reveal that high-pressure MSHCs always exhibit high energy densities.The range of theoretical energy density of CaH_(6)was predicted as 2.3-5.3 times of TNT,while the value for NbH_(3)was predicted as 1.2 times of TNT.Our study further uncover that CaH_(6)has outstanding energetic properties,which are ascribed to the three-dimensional(3D)aromatic H sublattice and the strong covalent bonding between the H atoms.Moreover,the detonation process and products of rapid energy-release stage of CaH_(6)were simulated via AIMD method,based on which its superior combustion performance was predicted and its specific impulse was calculated as 490.66 s.This study not only enhances the chemical understanding of MSHCs,but also extends the paradigm of traditional energetic materials and provides a new route to design novel high energy density materials.展开更多
基金supported by the UK EPSRC(Grant code:EP/V027255/1)the Leverhulme Trust(Grant code:RPG-2024-116)the computing service pro-vided by the UK National Service for Computational Chemistry Software(NSCCS)tendered by the Imperial College.
文摘The formation of stable neutral helium-and neon-containing compounds under ambient conditions remains a signifi-cant challenge in chemistry.Here we de-velop a novel strategy for the synthesis of helium-and neon-containing complex-es with a helium or neon atom encapsu-lated by two molecules with large elec-tric dipole moments.Using high-level ab initio calculations,we find that linear compounds,such as LiF-He-CuF,HCN-He-CuF,NaF-Ne-CuF,LiF-Ne-AuF and NaF-Ne-AuF,are stable,and the strong interac-tions resulting from the head-to-tail alignment of large electric dipoles have significantly en-hanced the He/Ne-metal binding when compared with those predicted for the He-CuF and Ne-AuF complexes.A viable experimental approach to synthesize these compounds is also out-lined,offering a potential route to stable neutral compounds containing both helium and neon under ambient conditions.
文摘A Bench top Quadrupole Mass Spectrometer System for Accurate Analysis of Trace Noble Gas was introduced in this paper. The inlet system was a especially designed one. And a capacitance pressure gauge with its linearity less than 0.01% was used to measure the fixed volume sample ratio. By using the calibration gas with the uncertainty of which less than 0.1% ,isotope condensed diluent could be quantified online. The procedure is done by alternate online mixture gas measurement of diluent gas, calibration gas to quantify the diluent gas, and diluent gas, sample gas to quantify the sample gas. The precision of six inlet from the same sample is +_0.13%0; The precision of six getting sample from the same source is less than ±0.5%. Self test was done by testing the mixture gas got with weighing method, in which consists Kr and Xe of 30 mg/kg. The system uncertainty tested to be below ±1%.
文摘A new approach to the quatitative analysis of Kr and Xe by isotope dilution mass spectrometry (IDMS) has been developed using inductively coupled plasma mass spectrometry (ICP-MS). The typical relative standard uncertainties of Kr and Xe IDMS are 1%.
文摘Metal superhydride compounds(MSHCs)have attracted much attention in the fields of high-pressure physics due to the superconductivity properties deriving from the metallic-hydrogen-like characteristics and relatively mild synthesis conditions.However,their energetic performance and related potential applications are still open issues till now.In this study,CaH_(6)and NbH_(3),which exhibit evidently differences in their geometric and electronic structures,were chosen as examples of MSHCs to investigate their energetic performance.The structure,bonding features and energetic performance of CaH_(6)and NbH_(3)were predicted based on first-principles calculations.Our results reveal that high-pressure MSHCs always exhibit high energy densities.The range of theoretical energy density of CaH_(6)was predicted as 2.3-5.3 times of TNT,while the value for NbH_(3)was predicted as 1.2 times of TNT.Our study further uncover that CaH_(6)has outstanding energetic properties,which are ascribed to the three-dimensional(3D)aromatic H sublattice and the strong covalent bonding between the H atoms.Moreover,the detonation process and products of rapid energy-release stage of CaH_(6)were simulated via AIMD method,based on which its superior combustion performance was predicted and its specific impulse was calculated as 490.66 s.This study not only enhances the chemical understanding of MSHCs,but also extends the paradigm of traditional energetic materials and provides a new route to design novel high energy density materials.
