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The purification of p‐xylene (pX) from its xylene isomers represents a challenging but important industrial process. Herein, we report the efficient separation of pX from its ortho‐ and meta‐ isomers by a microporous calcium‐based metal–organic framework material (HIAM‐203) with a flexible skeleton. At 30 °C, all three isomers are accommodated but the adsorption kinetics of o‐xylene (oX) and m‐xylene (mX) are substantially slower than that of pX, and at an elevated temperature of 120 °C, oX and mX are fully excluded while pX can be adsorbed. Multicomponent column breakthrough measurements and vapor‐phase/liquid‐phase adsorption experiments have demonstrated the capability of HIAM‐203 for efficient separation of xylene isomers. Ab initio calculations have provided useful information for understanding the adsorption mechanism. [ABSTRACT FROM AUTHOR]

The purification of p‐xylene (pX) from its xylene isomers represents a challenging but important industrial process. Herein, we report the efficient separation of pX from its ortho‐ and meta‐ isomers by a microporous calcium‐based metal–organic framework material (HIAM‐203) with a flexible skeleton. At 30 °C, all three isomers are accommodated but the adsorption kinetics of o‐xylene (oX) and m‐xylene (mX) are substantially slower than that of pX, and at an elevated temperature of 120 °C, oX and mX are fully excluded while pX can be adsorbed. Multicomponent column breakthrough measurements and vapor‐phase/liquid‐phase adsorption experiments have demonstrated the capability of HIAM‐203 for efficient separation of xylene isomers. Ab initio calculations have provided useful information for understanding the adsorption mechanism. [ABSTRACT FROM AUTHOR]

The full separation of alkane isomers as a function of different degrees of branching remains a daunting challenge due to its stringent requirement with respect to pore dimensions of the adsorbents. In this work, we report a novel microporous coordination network built on calcium (II) and chloranilate. The compound has a flexible framework and exhibits temperature‐dependent adsorption behavior toward hexane isomers. At 30 °C, it accommodates substantial amounts of linear and monobranched hexanes but fully excludes their dibranched isomer, and at elevated temperatures such as 150 °C, it acts as a splitter for linear and branched alkanes. Its capability of efficient discrimination of hexane isomers as a function of branching is verified by experimental breakthrough measurements. Ab initio calculations have uncovered the underlying selective size‐exclusion separation mechanism. [ABSTRACT FROM AUTHOR]

The full separation of alkane isomers as a function of different degrees of branching remains a daunting challenge due to its stringent requirement with respect to pore dimensions of the adsorbents. In this work, we report a novel microporous coordination network built on calcium (II) and chloranilate. The compound has a flexible framework and exhibits temperature‐dependent adsorption behavior toward hexane isomers. At 30 °C, it accommodates substantial amounts of linear and monobranched hexanes but fully excludes their dibranched isomer, and at elevated temperatures such as 150 °C, it acts as a splitter for linear and branched alkanes. Its capability of efficient discrimination of hexane isomers as a function of branching is verified by experimental breakthrough measurements. Ab initio calculations have uncovered the underlying selective size‐exclusion separation mechanism. [ABSTRACT FROM AUTHOR]

• Laser cooling schemes are built for the PbH, PoH, BiH+, and AtH+ molecules. • SOC splitting states are used for the closed transitions with high diagonal FCFs. • Accurate PECs are obtained using KRCI based on four-component relativistic orbitals. • The spectroscopic parameters correspond to the available experimental data. The pseudo-closed transition with enough large Frank-Condon factor (FCF) is a necessary condition for direct laser cooling molecules, which means that only a few molecules with the appropriate ground and excited electronic states can be considered as potential candidates. The electronic and spectroscopic properties of five Ω states are evaluated for the PbH, PoH, BiH+, and AtH+ molecules based on the four-component full relativistic calculations with all-electron basis sets, by which we construct optical schemes for these molecules by using the X 1 2Π 1/2 (ν'') ↔ X 2 2Π 3/2 (ν') transitions for PbH and BiH+ or the X 1 2Π 3/2 (ν'') ↔ X 2 2Π 1/2 (ν') ones for PoH and AtH+. The built schemes can provide 104 ∼ 105 scattering phonons with three or five pumping lasers. Moreover, the Doppler/recoil temperatures are 2.08 × 10−3/0.04, 2.91 × 10−3/0.11, 7.48 × 10−3/0.08 and 0.01/0.18 μK, respectively, which means that the temperature of the order of nanokelvin for the PbH and PoH and microkelvin for the BiH+ and AtH+ molecules may be cooled based on the present optical schemes. [Display omitted] [ABSTRACT FROM AUTHOR]