Trace water that gets into organic solvents can participate actively when molecules start to self-assemble

Cation gets a conductivity boost by capturing its counterion

A three-dimensional hydrogen-bonded network based on a rare mok topology has been constructed using an organic molecule synthesized in the solid state. The molecule is obtained using a supramolecular protecting-group strategy that is applied to a solid-state [2+2] photodimerization. The photodimerization affords a novel head-to-head cyclo­butane product. The cyclo­butane possesses tetrahedrally disposed cis-hydrogen-bond donor (phenolic) and cis-hydrogen-bond acceptor (pyridyl) groups. The product self-assembles in the solid state to form a mok network that exhibits twofold interpenetration. The cyclo­butane adopts different conformations to provide combinations of hydrogen-bond donor and acceptor sites to conform to the structural requirements of the mok net.

The disposition of functional groups can induce variations in the nature and type of interactions and hence affect the molecular recognition and self-assembly mechanism in cocrystals. To better understand the formation of cocrystals on a molecular level, the effects of disposition of functional groups on the formation of cocrystals were systematically and comprehensively investigated using cresol isomers (o-, m-, p-cresol) as model compounds. Consistency and variability in these cocrystals containing positional isomers were found and analyzed. The structures, molecular recognition and self-assembly mechanism of supramolecular synthons in solution and in their corresponding cocrystals were verified by a combined experimental and theoretical calculation approach. It was found that the heterosynthons (heterotrimer or heterodimer) combined with O—H⋯N hydrogen bonding played a significant role. Hirshfeld surface analysis and computed interaction energy values were used to determine the hierarchical ordering of the weak interactions. The quantitative analyses of charge transfers and molecular electrostatic potential were also applied to reveal and verify the reasons for consistency and variability. Finally, the molecular recognition, self-assembly and evolution process of the supramolecular synthons in solution were investigated. The results confirm that the supramolecular synthon structures formed initially in solution would be carried over to the final cocrystals, and the supramolecular synthon structures are the precursors of cocrystals and the information memory of the cocrystallization process, which is evidence for classical nucleation theory.

Among different types of polymorphism, disappearing polymorphism deals with the metastable kinetic form which can not be reproduced after its first isolation. In the world of coordination polymers (CPs) and metal–organic frameworks (MOFs), despite the fact that many types of supramolecular isomerism exist, we are unaware of disappearing supramolecular isomerism akin to disappearing polymorphism. This work reports a MOF with dia topology that could not be reproduced, but subsequent synthesis yielded another supramolecular isomer, a double-pillared-layer MOF. When perylene was added in the same reaction, the disappeared dia MOF reappeared with perylene as a guest in the channels. Interestingly, the photoluminescence of the dia MOF with a perylene guest is dominated by the emission of the guest molecule. The influence of guest molecules on the stabilization of the supramolecular isomers of a MOF opens up a strategy to access MOFs with different structures.

Компания Meizu провела в Китае мероприятие, на котором анонсировала свою новую флагманскую линейку смартфонов — Meizu 17.

After a lengthy teaser campaign, Meizu finally unveiled its latest flagships with the Meizu 17 and 17 Pro. Spec-wise the two are nearly identical with the Pro featuring better auxiliary cameras, wireless charging and faster RAM. Visually the two are also almost indistinguishable with the only difference being the 17 Pro comes with a ceramic back. These are also the first 5G entries in Meizu's lineup. The Meizu 17 duo is built around 6.6-inch Super AMOLED displays with 90Hz refresh rate and a first for Meizu punch-hole cutout for the 20MP selfie camera. The panels come with an...

The Indian government in March put a hold on exports of several drugs including paracetamol to secure supplies for its people after the coronavirus outbreak disrupted the industry's supply chain globally. COVID-19 is the respiratory disease caused by the novel coronavirus.

[News24Wire] Only offenders who committed petty crimes will be eligible to be included in the 19 000 inmates who will be released on parole to combat the spread of Covid-19 in prisons.

visit News18 Urdu for latest news, breaking news, news headlines and updates from Chamoli on politics, sports, entertainment, cricket, crime and more.

Because store-bought guacamole has too much packaging and potentially strange ingredients; and bad homemade guacamole is sad.

Kanpur administration has directed all pharmacies to register the name, address and contact number of people buying paracetamol or medicines for cough, cold and fever or breathing problems.

Julia Walentin, 26, who lives in South London, tried to get an upgrade on her flight from Singapore by telling the flight crew she had a headache. However they then worried she had coronavirus.

टेक्नोलॉजी और गैजेट्स से जुड़े ऐसे कई शब्द हैं, जिनके बारे में हमें जानकारी नहीं होती। इनमें ज्यादातर शब्द तो हमारे द्वारा डेली इस्तेमाल किए जाने वाले स्मार्टफोन से जुड़े होते हैं। ऐसे में हम टेक गाइड की मदद से आपको इन शब्दों के मतलब समझा रहे हैं।

कैपेसिटिव टचस्क्रीन LCD : कैपेसिटिव टचस्क्रीन मानव शरीर के इलेक्ट्रिकल प्रॉपर्टीज के सेंसिंग से काम करता है। कैपेसिटिव टचस्क्रीन पैनल में इंडियम टिन ऑक्साइड के ट्रांसपैरेंट कंडक्टर होता है। ह्यूमन बॉडी में भी इलेक्ट्रिकल कंडक्टर होता है, जिससे स्क्रीन को टच करने सें इलेक्ट्रोस्टेटिक फील्ड रिस्टोर हो जाता है और वह प्वाइंट इन्सट्रक्शन के रूप में लिए जाता है। कैपेसिटिव टचस्क्रीन, रेजिस्टिव टचस्क्रीन से काफी बेहतर है।

OLED : OLED का मतलब Organic Light-Emitting Diode है। OLED में ऑर्गेनिक पॉलिमर के छोटे डॉट्स होते हैं, जो इलेक्ट्रिसिटी से चार्ज होने के बाद लाइट को डेवलप करते हैं। OLED नइ डिस्प्ले टेक्नोलॉजी है, जो LCD के मुकाबले कम पावर लेती है और यह पतली, हल्की, बेहतर व्यूइंग एंगल और वीडियो और एनिमेशन के लिए अच्छा रिस्पांस टाइम है। ओएलईडी स्क्रीन में खुद एलईडी ही पिक्सल का काम करती हैं और 6 लेयर्स मिलकर तस्वीरें स्क्रीन पर लाती हैं। इसलिए ओएलईडी टीवी पर तस्वीर ज्यादा स्पष्ट दिखती है और किसी भी एंगल से देखने पर एक सा दिखाई देता है। साथ ही ओएलईडी स्क्रीन वाले गैजेट्स काफी पतले और हल्के होते हैं।

AMOLED : AMOLED एक्टिव मैट्रिक्स ऑर्गेनिक लाइट एमिटिंग डायोड है। यह मोबाइल फोन और टीवी के लिए नेक्स्ट जनरेशन डिस्प्ले टेक्निक है। यह एलसीडी की तुलना में रिच कलर, शार्पर इमेज, कम पॉवर कन्जूमशन और अधिक पतली और हल्की है।

सुपर AMOLED : सुपर AMOLED को पारंपरिक AMOLED के मुकाबले बेहतर परफॉरमेंस हे लिए तैयार किया गया है। AMOLED की तुलना में सीधे धूप में देखे जाने पर सुपर AMOLED का परफॉरमेंस अच्छा है और यह ब्राइट इमेज को सपोर्ट करता है और पॉवर कम लगती है।