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81.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Yan Zhang Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o59-o62
In the syn‐ and anticlinal isomers of the title compound, C22H18N2O6, the indole moiety is not completely planar, with the pyrrolidine ring being distorted very slightly towards a conformation intermediate between half‐chair and envelope. The molecular and packing structures in the crystals of these isomers are stabilized by C—H?O interactions. 相似文献
82.
Nicholas A. Barnes Stephen M. Godfrey Ruth T.A. Halton Imrana Mushtaq Simon Parsons Robin G. Pritchard Mark Sadler 《Polyhedron》2007
Structural and spectroscopic data on the series of compounds “PhSeX”, where X = Cl, CN or SCN, are reported and compared with previously reported data on “PhSeX” systems (X = Br and I). The chloro-compound displays a “square” motif, Ph4Se4Cl4, in the solid state, linked by long Se–Se bonds [2.993(3)–3.035(3) Å], and forms a loosely held network of Se4 and Cl4 squares in its extended structure. In contrast, the pseudohalogen derivatives, PhSeCN and PhSeSCN, consist of essentially monomeric units, which form chains held together by weak Se?N interactions in the solid state. These Se?N interactions are much shorter in PhSeCN, 3.023(3)–3.065(4) Å, than in PhSeSCN, 3.348(4) Å. Weaker Se?N contacts are also present between the chains. The structure of PhSeSCN described here is the first reported crystallographic study of a selenium thiocyanate compound. Spectroscopic studies suggest that all three compounds exist as monomers in solution. The results reported herein illustrate the subtle differences in the solid-state structures of PhSeX compounds. 相似文献
83.
Muhammad Arif Ghulam Yasin Muhammad Shakeel Muhammad Asim Mushtaq Wen Ye Xiaoyu Fang Shengfu Ji Dongpeng Yan 《Journal of Energy Chemistry》2021,(7):237-246
Production of hydrogen (H2) and oxygen (O2) through electrocatalytic water splitting is one of the sustainable,green and pivotal ways to accomplish the ever-inc... 相似文献
84.
Anwar Usman Ibrahim Abdul Razak Suchada Chantrapromma Sujit K. Ghorai Dipakranjan Mal Hoong‐Kun Fun Gur Dayal Nigam 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1118-1119
The title compound, C19H16O, crystallizes with two molecules of opposite chirality in the asymmetric unit. In both molecules, the naphthalene and cyclopentanone moieties are individually planar. The two cyclopentane rings adopt envelope conformations, while the cyclohexane ring adopts a boat conformation. 相似文献
85.
Dr. Muhammad Usman Khan Dr. Muhammad Imran. Dr. Muhammad Fayyaz ur Rehman Dr. Mohammed A. Assiri Dr. Syed Muddassir Ali Mashhadi Dr. Muhammad Safwan Akram Dr. Changrui Lu 《ChemistryOpen》2022,11(8)
Porphyrin‐based non‐fullerene acceptors (NFAs) have shown pronounced potential for assembling low‐bandgap materials with near‐infrared (NIR) characteristics. Herein, panchromatic‐type porphyrin‐based molecules (POR1–POR5) are proposed by modulating end‐capped acceptors of a highly efficient porphyrin‐based NFA PORTFIC(POR) for organic solar cells (OSCs). Quantum chemical structure‐property relationship has been studied to discover photovoltaic and optoelectronic characteristics of POR1–POR5. Results show that optoelectronic properties of the POR1–POR5 are better in all aspects when compared with the reference POR. All proposed NFAs particularly POR5 proved to be the preferable porphyrin‐based NIR sensitive NFA for OSCs applications owing to lower energy gap (1.56 eV), transition energy (1.11 eV), binding energy (Eb =0.986 eV), electron mobility (λe=0.007013Eh ), hole mobility (λh =0.004686 Eh), high λmax =1116.27 nm and open‐circuit voltage (Voc =1.96 V) values in contrast to the reference POR and other proposed NFAs. This quantum chemical insight provides sufficient evidence about excellent potential of the proposed porphyrin‐based NIR sensitive NFA derivatives for their use in OSCs. 相似文献
86.
(R)‐2,3‐Cyclohexylideneglyceraldehyde,a Chiral Pool Synthon for the Synthesis of 2‐Azido‐1,3‐diols 下载免费PDF全文
Abdul Rouf Mushtaq A. Aga Brijesh Kumar Subhash C. Taneja 《Helvetica chimica acta》2015,98(6):823-833
A new approach was proposed for the synthesis of 2‐azido‐1,3‐diols from easily available and inexpensive chiral pool synthon (R)‐2,3‐O‐cyclohexylidene‐D ‐glyceraldehyde, through Mitsunobu azidation of 1,2‐diols. Both C(2) and C(1) azides in variable ratios were obtained in alkyl substituted diols with C(2) as the major one. 相似文献
87.
Muhammad Usman Ghani Muhammad Sagir Muhammad Bilal Tahir Sami Ullah Mohammed Ali Assiri 《International journal of quantum chemistry》2024,124(3):e27340
Halide base perovskite LiCdX3 (X = F, Cl) is tested by CASTEP (Cambridge Serial Total Energy Package) based on density function theory (DFT). The presented discussion is to explore the structural, electronic, and optical properties of LiCdX3 (X = F, Cl). The calculated values of the lattice parameter are found to be 3.8 Å and 5.27 Å of LiCdF3 and LiCdCl3 respectively. The ideal structure of LiCdX3 (X = F, Cl) is cubic and dynamically stable. Electronic properties show that materials are semiconductors. The results from band structure are further evaluated by the total and partial density of states. The partial and total density of states confirms the degree of localization of electrons. In optical properties, the highest absorption coefficient is observed in LiCdCl3. The material is half metallic and has a narrow indirect band gap which may be used in photovoltaic applications. 相似文献
88.
A. Mushtaq Sh. Pervez I. Haider M. S. Mansur M. Jehangir 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(3):827-829
99mTc pentavalent dimercaptosuccinic acid [99mTc(V) DMSA], a useful agent for imaging thyroid medullary carcinoma and other tumors can be reliably prepared by addition of Na99mTcO4 to a freeze-dried mixture of DMSA and Sn (2:1 molar ratio). The radiochemical purity, stability and animal bio-distribution behaviour is similar to that of the agent made by addition of NaHCO3 to DMSA (III) renal imaging freeze-dried kit. 相似文献
89.
90.
Free space optics (FSO) is a promising communication technique for various types of services in the optical access network. Single beam FSO system in tropical rainy weather is vulnerable to atmospheric rain attenuation, so it is necessary to have precise power law parameters of rain attenuation in tropical regions. In this study, the power law parameters k, and α are estimated as 2.03 and 0.74, respectively for the FSO applications in tropical South-East Asian weather. These parameters were evaluated by using least square mean equation (LSME) method with Levenberg–Marquardt optimization based on the one year collected heavy rain data. The obtained parameter values for tropical weather are contributed to improve link performance for high-speed networks. 相似文献