Probing the Excited Electronic Configuration and Associative Excitons in Pyrene‐Based X‐Ray Scintillating MOF Excimer: Bridging the Gap Between Theory and Experiments

Abstract

Scintillators are essential in converting ionizing X‐rays and γ‐rays into visible light, with applications in medical diagnosis, security inspection, and non‐invasive detection. However, current scintillating materials exhibit unclear structure–function relationships. The performance of scintillators is intricately linked to their electronic band structure, particularly the intrinsic properties of excited states. Therefore, investigating the structural factors affecting scintillation performance is crucial for developing new scintillators. Therefore, Ba‐SMOF 1 ([Ba2(PyTS)(CH3OH)2(H2O)4]n) is synthesized using a pyrene‐based organic motif and metal Ba(II) ions, where PyTS4− refers to pyrene‐1,3,6,8‐tetrasulfonate. For the first time, the excited state of a pyrene‐based X‐ray scintillating metal–organic framework (MOF) is determined through comprehensive all‐electron excitation studies, including in situ experimental electron density and wave‐function analysis. The electron density maps exhibit a continuous overlap, attributed to the associative exciton behaviors among the closely packed PyTS4− linkers. These linkers are identified as the sources of both static and dynamic excimer emissions. The electron density studies reveal the role of excimers in pyrene‐based luminophores, highlighting that interchromophoric interactions are key to enhancing the performance of scintillating MOFs. This discovery opens new avenues for the practical application of scintillating MOFs.

Enhanced X-ray Imaging with Gd2O2S:Pr-Epoxy Composite Films: Synthesis, High-Resolution Performance, and Flexibility

“…Scintillation materials, which emit light when excited by high-energy particles, are available in various forms, including organic, − inorganic, − and organic–inorganic composite scintillators. , Organic scintillators offer quick response and flexibility but suffer from lower efficiency and radiation resistance. − In contrast, inorganic scintillators deliver higher efficiency and durability but at a higher cost and with fabrication limitations. − Organic–inorganic composite scintillators, combining organic substances with inorganic scintillation components, offer a promising solution by merging the benefits of both types, such as cost-effectiveness and tunable scintillation properties . These advantages of organic–inorganic composite scintillators make them suitable for practical applications in X-ray panel imaging.…”

Optimized Gd2O2S:Pr Scintillation Films for X-ray Flat Panel Imaging: Balancing Enhanced Efficiency with Flexibility

“…Particularly, the development of perovskite nanocrystals in recent years has attracted significant attention toward flexible scintillation films. − However, the light yield of perovskite nanocrystal scintillators remains inferior in comparison to traditional bulk scintillation materials owing to their small Stokes shift and strong self-absorption . Inspired by flexible perovskite nanocrystal scintillation films, the combination of traditional granular scintillators with an organic polymer matrix has the potential to yield similar benefits. − Praseodymium-doped gadolinium oxysulfide (Gd 2 O 2 S:Pr) exhibits excellent characteristics, including high intrinsic X-ray to light conversion efficiency, rendering it suitable for X-ray imaging applications. − Although Gd 2 O 2 S:Pr phosphors or ceramic scintillators have been successfully applied in flat panels and CT detectors, flexible scintillation films based on Gd 2 O 2 S:Pr phosphors have seldom been reported …”