An Extra‐Large‐Pore Zeolite with 24×8×8‐Ring Channels Using a Structure‐Directing Agent Derived from Traditional Chinese Medicine

Abstract

Extra-large-pore zeolites have attracted much interest because of their important applications for processing larger molecules. Although great progress has been made in academic science and industry, it is challenging to synthesize these materials. A new extra-large-pore zeolite SYSU-3 (Sun Yat-sen University no. 3) has been synthesized by using a novel sophoridine derivative as an organic structure-directing agent (OSDA). The framework structure was solved and refined using continuous rotation electron diffraction (cRED) data from nanosized crystals. SYSU-3 exhibits a new zeolite framework topology, which has the first 24×8×8-ring extra-large-pore system and a framework density (FD) as low as 11.4 T/1000 Å . The unique skeleton of the OSDA plays an essential role in the formation of the distinctive zeolite structure. This work provides a new perspective for developing new zeolitic materials by using alkaloids as cost-effective OSDAs.

Rapid Structure Determination of Microcrystalline Molecular Compounds Using Electron Diffraction

“…[16][17][18][19][20] Microcrystalline powders outnumber single-crystal compounds by afactor of 3to4(we refer to the term "microcrystalline" as "composed of small crystals", for example,s uitable for X-ray powder diffrac-tion). [9,[28][29][30][31] To date,e lectron crystallography only plays am inor role in structural chemistry.A so fS eptember 2018, the Inorganic Crystal Structure Database contained 425 single-crystal structures from electron crystallography compared with over 78 500 structures from X-ray crystallography. [22,23] Structure determination with electron crystallography comes at ap rice:A na ccurate description of the interaction process between electron radiation and acrystal is based on the dynamical theory of diffraction, [24,25] which is more complex than kinematic diffraction, the basis of X-ray crystallography.…”

“…[27] However,t ime and effort for dynamic refinement are generally impractical considering the throughput in most structural chemistry facilities both in academia and in industry.F ortunately,i gnoring dynamic scattering does not lead to loss in model accuracy,b ut only to worse model and data statistics,s ot hat additional validation criteria must be provided. [9,[28][29][30][31] To date,e lectron crystallography only plays am inor role in structural chemistry.A so fS eptember 2018, the Inorganic Crystal Structure Database contained 425 single-crystal structures from electron crystallography compared with over 78 500 structures from X-ray crystallography. [1] TheC ambridge Structural Database of organic structures does not even provide as earch mask for electron diffraction.…”

Schnelle Strukturaufklärung mikrokristalliner molekularer Verbindungen durch Elektronenbeugung

“…[16][17][18][19][20] Verbindungen, die als mikrokristallines Pulver vorliegen, übertreffen die Anzahl monokristalliner Stoffe um das 3-bis 4-fache. [9,[28][29][30][31] Bis dato spielte die Elektronenkristallographie nur eine untergeordnete Rolle in der Strukturchemie.ImSeptember 2018 enthielt die "Inorganic Crystal Structure Database" 425 Einkristallstrukturen, die mittels Elektronenkristallographie bestimmt wurden. [22,23] Die Strukturaufklärung durch Elektronenkristallographie hat ihren Preis: Eine genaue Beschreibung der Wechselwirkung zwischen Elektronenstrahlung und einem Kristall beruht auf der Theorie der dynamischen Beugung, [24,25] die komplexer ist als die kinematische Beugung,d er Grundlage der Rçntgenkristallographie.…”

“…Wird die dynamischen Beugung ignoriert, so führt dies allerdings nicht zum Verlust der Genauigkeit des Modells,s ondern nur zu schlechten Modell-und Datenstatistiken, sodass zusätzliche Va lidierungskriterien bereitgestellt werden müssen. [9,[28][29][30][31] Bis dato spielte die Elektronenkristallographie nur eine untergeordnete Rolle in der Strukturchemie.ImSeptember 2018 enthielt die "Inorganic Crystal Structure Database" 425 Einkristallstrukturen, die mittels Elektronenkristallographie bestimmt wurden. Diesen stehen 78 500 Rçntgenkristallstrukturen gegenüber.…”

InsteaDMatic: towards cross-platform automated continuous rotation electron diffraction

“…3D electron diffraction (3DED) and microcrystal electron diffraction (MicroED) have been shown to be powerful techniques for the structure determination of solids, and are especially advantageous for studies of micro-and nanocrystals. So far, hundreds of structures have been determined by 3DED (Gemmi et al, 2019), including zeolites (Jiang et al, 2011;Martínez-Franco et al, 2013;Guo et al, 2015;Simancas et al, 2016;Lee et al, 2018;Bieseki et al, 2018;Zhang et al, 2018;Smeets et al, 2019), metal-organic frameworks (Denysenko et al, 2011;Feyand et al, 2012;Wang, Rhauderwiek et al, 2018;Lenzen et al, 2019), pharmaceuticals Gruene et al, 2018;Jones et al, 2018;Brá zda et al, 2019), proteins (Nannenga et al, 2014;de la Cruz et al, 2017;Xu et al, 2019;Lanza et al, 2019) and many others.…”