Naphtho[2,1-<i>b</i>:6,5-<i>b</i>′]difuran: A Versatile Motif Available for Solution-Processed Single-Crystal Organic Field-Effect Transistors with High Hole Mobility

We here report naphtho­[2,1-<i>b</i>:6,5-<i>b</i>′]­difuran derivatives as new p-type semiconductors that achieve hole mobilities of up to 3.6 cm² V^–1 s^–1 along with high <i>I</i>_on/<i>I</i>_off ratios in solution-processed single-crystal organic field-effect transistors. These features originate from the dense crystal packing and the resulting large intermolecular π-orbital overlap as well as from the small reorganization energy, all of which originate from the small radius of an oxygen atom

Naphtho[2,1-<i>b</i>:6,5-<i>b</i>′]difuran: A Versatile Motif Available for Solution-Processed Single-Crystal Organic Field-Effect Transistors with High Hole Mobility

We here report naphtho­[2,1-<i>b</i>:6,5-<i>b</i>′]­difuran derivatives as new p-type semiconductors that achieve hole mobilities of up to 3.6 cm² V^–1 s^–1 along with high <i>I</i>_on/<i>I</i>_off ratios in solution-processed single-crystal organic field-effect transistors. These features originate from the dense crystal packing and the resulting large intermolecular π-orbital overlap as well as from the small reorganization energy, all of which originate from the small radius of an oxygen atom

Enhancement of the Exciton Coherence Size in Organic Semiconductor by Alkyl Chain Substitution

Photophysical properties of molecular aggregates are largely determined by exciton coherence size: a spatial extension of exciton delocalization. Increase in exciton coherence size can lead to fast energy transport as well as efficient charge separation. Here, we demonstrate that introducing alkyl chains to organic molecules can enhance the exciton coherence size significantly. Focusing on the thin films of excellent hole transport materials, dinaphtho­[2,3-<i>b</i>:2,3-<i>f</i>]­thieno­[3,2-<i>b</i>]­thiophene (DNTT) and its alkyl-substituted derivative, we analyze the steady-state and picosecond time-resolved photoluminescence spectra of the films to estimate exciton coherence sizes. The alkyl substitution enhances the coherence size by a factor of 2–3, indicating that a long-range ordering in the molecular aggregates is achieved with the additional van der Waals interaction between saturated alkyl chains. The coherence sizes of both the films decrease with increasing temperature owing to thermal populations within the vibronic exciton manifolds

Enabling Ambipolar to Heavy n‑Type Transport in PbS Quantum Dot Solids through Doping with Organic Molecules

PbS quantum dots (QDs) are remarkable semiconducting materials, which are compatible with low-cost solution-processed electronic device fabrication. Understanding the doping of these materials is one of the great research interests, as it is a necessary step to improve the device performance as well as to enhance the applicability of this system for diverse optoelectronic applications. Here, we report the efficient doping of the PbS QD films with the use of solution-processable organic molecules. By engineering the energy levels of the donor molecules and the PbS QDs through the use of different cross-linking ligands, we are able to control the characteristics of PbS field-effect transistors (FETs) from ambipolar to strongly n-type. Because the doping promotes trap filling, the charge carrier mobility is improved up to 0.64 cm² V^–1 s^–1, which is the highest mobility reported for low-temperature processed PbS FETs employing SiO₂ as the gate dielectric. The doping also reduces the contact resistance of the devices, which can also explain the origin of the increased mobility

موسى بن محمد قاضي زاده الرومي. أشكال التأسيس

Numérisation effectuée à partir d'un document de substitution.Commentaire des Aškāl al-ta'sīs de Muḥammad ibn Ašraf al-Samarqandī. Titre au f. 2. Inc. (f. 2v) : الحمد لله الذي خلق كل شيء بقدر وقدر له ما يليق من أشكال وصور... وبعد فإن الهندسة مع متانة مسائلها Exp. (f. 50v) : وهذه الأشكال الخمسة الأخيرة من ثانية كتاب الأصول لأقليدس وليكن هذا آخر الكلام وقد تم الكتاب Copie achevée par ʿAbd al-Qādir ibn Muṣṭafā al-Ḥallāq le 12 šawwāl 1176 h. / 26 avril 1763.Cachet et marque du commanditaire de la copie : Muḥammad ʿĀrif, mudarris à Dār al-Sulṭana, Marque de possession de Muḥammad ibn Ḥusayn (?) (f. 1). Indication de prix : 15 piastres (f. 1). Marque à l'encre violette datée du 3 šaʿbān 1361 h. / 16 août 1942, au nom de Muḥammad al-Amīn ibn Muḥammad ʿAbd Allāh (f. 1v

Boron-Stabilized Planar Neutral π‑Radicals with Well-Balanced Ambipolar Charge-Transport Properties

Organic neutral π-monoradicals are promising semiconductors with balanced ambipolar carrier-transport abilities, which arise from virtually identical spatial distribution of their singly occupied and unoccupied molecular orbitals, SOMO­(α) and SOMO­(β), respectively. Herein, we disclose a boron-stabilized triphenylmethyl radical that shows outstanding thermal stability and resistance toward atmospheric conditions due to the substantial spin delocalization. The radical is used to fabricate organic Mott-insulator transistors that operate at room temperature, wherein the radical exhibits well-balanced ambipolar carrier transport properties

Boron-Stabilized Planar Neutral π‑Radicals with Well-Balanced Ambipolar Charge-Transport Properties

Organic neutral π-monoradicals are promising semiconductors with balanced ambipolar carrier-transport abilities, which arise from virtually identical spatial distribution of their singly occupied and unoccupied molecular orbitals, SOMO­(α) and SOMO­(β), respectively. Herein, we disclose a boron-stabilized triphenylmethyl radical that shows outstanding thermal stability and resistance toward atmospheric conditions due to the substantial spin delocalization. The radical is used to fabricate organic Mott-insulator transistors that operate at room temperature, wherein the radical exhibits well-balanced ambipolar carrier transport properties

Single-Molecule Observation of Redox Reactions Enabled by Rigid and Isolated Tripodal Molecules

Tracking various chemical reactions, including electrochemical and photochemical reactions at the single-molecule level, is expected to yield a great deal of knowledge from both fundamental and applied aspects. In this study, we report on a methodology to track the electronic-state changes of redox reactions at the single-molecule level by using electrochemical scanning tunneling microscopy (EC-STM). EC-STM is powerful for single-molecule analysis of redox reactions, but previous studies have shown difficulties separating the structural and electronic contributions due to orientational changes during the redox reaction. Here, we visualize the electronic-state changes of a single ferrocene associated with redox reactions using EC-STM by synthesizing and fabricating a monolayer of structurally rigid tripodal molecules based on triptycene, which act as ideal anchors to preserve a constant distance between the electrode and the ferrocene moieties. This methodology paves the way for versatile single-molecule measurements of important phenomena at the solid–liquid interface, such as photochemistry and heterogeneous catalysis

Single-Molecule Observation of Redox Reactions Enabled by Rigid and Isolated Tripodal Molecules

Tracking various chemical reactions, including electrochemical and photochemical reactions at the single-molecule level, is expected to yield a great deal of knowledge from both fundamental and applied aspects. In this study, we report on a methodology to track the electronic-state changes of redox reactions at the single-molecule level by using electrochemical scanning tunneling microscopy (EC-STM). EC-STM is powerful for single-molecule analysis of redox reactions, but previous studies have shown difficulties separating the structural and electronic contributions due to orientational changes during the redox reaction. Here, we visualize the electronic-state changes of a single ferrocene associated with redox reactions using EC-STM by synthesizing and fabricating a monolayer of structurally rigid tripodal molecules based on triptycene, which act as ideal anchors to preserve a constant distance between the electrode and the ferrocene moieties. This methodology paves the way for versatile single-molecule measurements of important phenomena at the solid–liquid interface, such as photochemistry and heterogeneous catalysis

Single-Molecule Observation of Redox Reactions Enabled by Rigid and Isolated Tripodal Molecules

Tracking various chemical reactions, including electrochemical and photochemical reactions at the single-molecule level, is expected to yield a great deal of knowledge from both fundamental and applied aspects. In this study, we report on a methodology to track the electronic-state changes of redox reactions at the single-molecule level by using electrochemical scanning tunneling microscopy (EC-STM). EC-STM is powerful for single-molecule analysis of redox reactions, but previous studies have shown difficulties separating the structural and electronic contributions due to orientational changes during the redox reaction. Here, we visualize the electronic-state changes of a single ferrocene associated with redox reactions using EC-STM by synthesizing and fabricating a monolayer of structurally rigid tripodal molecules based on triptycene, which act as ideal anchors to preserve a constant distance between the electrode and the ferrocene moieties. This methodology paves the way for versatile single-molecule measurements of important phenomena at the solid–liquid interface, such as photochemistry and heterogeneous catalysis