Results 191 to 200 of about 3,584 (216)

Cation rotation in methylammonium lead halides

Solid State Communications, 1985
Abstract 2 H and 14 N nmr spectra of the simple perovskites CH 3 NH 3 PbX 3 (X = Cl >, Br, I) reveal the existence of several phases. In the high-temperature phase I the long spin-lattice relaxation times T 1 of both nuclei and the absence of quadrupole splitting indicate extremely rapid overall reorientation of the CN axis of the cation in ...
R.E. Wasylishen, Osvald Knop, J.B. Macdonald   +2 more
openaire   +1 more source

Self-Alignment of the Methylammonium Cations in Thin-Film Organometal Perovskites

The Journal of Physical Chemistry Letters, 2014
A comparative study of the electronic structure of methylammonium (CH3NH3) in organometallic lead triiodide perovskite (CH3NH3PbI3) thin films synthesized using either one- or two-step deposition protocols is performed using angle-resolved C K-edge soft X-ray absorption spectroscopy (XAS) and model calculations. We find that our XAS measurements can be
John A, McLeod, Zhongwei, Wu, Pengfei, Shen, Baoquan, Sun, Lijia, Liu   +4 more
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Components of the interaction energy of benzene with Na+ and methylammonium cations

Journal of Molecular Structure: THEOCHEM, 2001
The results of ab initio computations including correlation (MP2) performed on the complexes of Na+, monomethylammonium (MMA) and tetramethylammonium (TMA) with a same ligand, benzene, are compared at the same theoretical level (double-zeta basis set, with polarization functions optimized on molecular polarizabilities).
A Pullman, G Berthier, R Savinelli
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Extraction and DFT study on the complexation of the methylammonium cation with a hexaarylbenzene-based receptor

Journal of Radioanalytical and Nuclear Chemistry, 2013
Abstract  From extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium Cs+(aq) + A−(aq) + 1(nb) ⇆ 1·Cs+(nb) + A− (nb) taking part in the two-phase water–nitrobenzene system (A− = picrate, 1 = hexaarylbenzene-based receptor; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K ex (1·Cs+,
E. Makrlík, P. Toman, P. Vaňura, R. Rathore   +3 more
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Vibrational Response of Methylammonium Lead Iodide: From Cation Dynamics to Phonon–Phonon Interactions

ChemSusChem, 2016
AbstractThe dynamic evolution of the vibrational interactions in the prototypical CH3NH3PbI3 was studied through a comprehensive experimental and theoretical investigation with a focus on the interactions between the organic cations and the inorganic cage.
Ivanovska, TanjaQuarti, ClaudioGrancini, GiuliaPetrozza, AnnamariaDe Angelis, FilippoMilani, AlbertoRuani, Giampiero   +7 more
openaire   +5 more sources

Self-diffusion of methylammonium cations in the high-temperature solid phase of CH3NH3NO3

Journal of the Chemical Society, Faraday Transactions 2, 1985
The high-temperature solid phase of CH3NH3NO3, which is stable above 352 K, has been studied by differential thermal analysis, differential scanning calorimetry, X-ray powder diffraction, 1H nuclear magnetic resonance spectroscopy and electrical-conductivity experiments. X-ray powder patterns taken at 370 K reveal that CH3NH3NO3 forms a CsCl-type b.c.c.
Hiroyuki Ishida, Ryuichi Ikeda, Daiyu Nakamura   +2 more
openaire   +1 more source

Steric Mixed‐Cation 2D Perovskite as a Methylammonium Locker to Stabilize MAPbI₃

Angewandte Chemie, 2019
AbstractThe reduced dimension perovskite including 2D perovskites are one of the most promising strategies to stabilize lead halide perovskite. A mixed‐cation 2D perovskite based on a steric phenyltrimethylammonium (PTA) cation is presented. The PTA‐MA mixed‐cation 2D perovskite of PTAMAPbI4 can be formed on the surface of MAPbI3 (PTAI‐MAPbI3) by ...
Xingtao Wang, Yong Wang, Taiyang Zhang, Xiaomin Liu, Yixin Zhao   +4 more
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A Cation‐Exchange Approach for the Fabrication of Efficient Methylammonium Tin Iodide Perovskite Solar Cells

Angewandte Chemie, 2019
AbstractTin‐based halide perovskite materials have been successfully employed in lead‐free perovskite solar cells, but the overall power conversion efficiencies (PCEs) have been limited by the high carrier concentration from the facile oxidation of Sn2+ to Sn4+. Now a chemical route is developed for fabrication of high‐quality methylammonium tin iodide
Fengzhu Li, Chaoshen Zhang, Jin‐Hua Huang, Haochen Fan, Huijia Wang, Pengcheng Wang, Chuanlang Zhan, Cai‐Ming Liu, Xiangjun Li, Lian‐Ming Yang, Yanlin Song, Ke‐Jian Jiang   +11 more
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Orientational preference of the organic cations in methylammonium lead-iodide perovskite: the role of structural constraints

Chemical Physics Letters, 2020
Abstract We have investigated the influence of organic–inorganic interactions in methylammonium lead-iodide by employing density functional theory (DFT). These results provide a unified picture for the orientational stability of MA in MAPbI3: (cell edge) [0 1 1] > (face centre) [1 0 0] ≈ (diagonal) [1 1 1], which is in good agreement with the ...
Saqib Javaid, Khaqan Shati, Rao Tahir Ali Khan, Muhammad Javed Akhtar   +3 more
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Methylammonium cation deficient surface for enhanced binding stability at TiO2/CH3NH3PbI3 interface

Nano Research, 2016
Heterojunction interfaces in perovskite solar cells play an important role in enhancing their photoelectric properties and stability. Till date, the precise lattice arrangement at TiO2/CH3NH3PbI3 heterojunction interfaces has not been investigated clearly.
Xin Xu, Kai Li, Zhenzhong Yang, Jiangjian Shi, Dongmei Li, Lin Gu, Zhijian Wu, Qingbo Meng   +7 more
openaire   +1 more source