Publications by authors named "Adrian M Mak"

Photosynthesis has been shown to be a highly efficient process for energy transfer in plants and bacteria. Like natural photosynthetic systems, the artificial light harvesting complex (LHC) BODIPY pillar[5]arene exhibits Förster resonance energy transfer (FRET). However, extensive characterisation of the BODIPY pillar[5]arene LHC to determine its suitability as an artificial LHC has yet to occur.

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One of key factors to design applicable electron transport layers (ETLs) for perovskite solar cells is the morphology of ETLs since a good morphology would help to facilitate the carrier transport at two interfaces (perovskite\ETL and ETL\cathode). However, one drawback of most organic ETL small molecules is the internal undesired accumulation, which would cause the formation of inappropriate morphology and rough ETL surface. Here, by elaborately designing the side chains of NDI derivatives, the molecular interaction could be modified to achieve the aggregation in different degrees, which would eventually affect the accumulation of molecules and surface qualities of ETLs.

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Developing air-stable high-performance small organic molecule-based n-type and ambipolar organic field-effect transistors (OFETs) is very important and highly desirable. In this investigation, we designed and synthesized two naphthalenediimide (NDI) derivatives (NDI-BTH1 and NDI-BTH2) and found that introduction of 2-(benzo[]thiazol-2-yl) acetonitrile groups at the NDI core position gave the lowest unoccupied molecular orbital (LUMO; -4.326 eV) and displayed strong electron affinities, suggesting that NDI-BTH1 might be a promising electron-transporting material (i.

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Many biological processes are driven by the interaction of a host with a guest molecule. We show such interactions can be modulated by carefully defining the local molecular environment to give a specific chemical outcome. Particularly, the selectivity of a host toward two different ions (Ca and Al) is defined by it being in solution or the physisorbed state.

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The recently developed adiabatic absolutely localized molecular orbital energy decomposition analysis (ALMO-EDA) has proven to be useful in determining the effects of different energy components on the geometries of complexes bound by intermolecular interactions. The authors have applied it to systems such as the water dimer, water-ion complexes, metallocenes and lone-pair type halogen-bonded (XB) dimers. In this study, we have extended the second-generation ALMO-EDA method to 40 different XB complexes by benchmarking against its classical counterpart and symmetry-adapted perturbation theory (SAPT).

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Halogen bonding (XB) has become one of the most studied non-covalent interactions in the past two decades, owing to its wide range of applications in materials and biological applications. Most of the current theoretical and experimental studies focus on XB involving lone-pair acceptors due to its predictability in terms of crystal geometries. However, recent reports have advocated the importance of XB materials involving aromatic-type acceptors because of their relevance in functional materials, catalysis and biological systems.

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A mild, oxidant-free, and selective Cp*Co -catalyzed amidation of thioamides with robust dioxazolone amidating agents via C(sp )-H bond activation to generate the desired amidated products is reported. The method is efficient and allows for the C-H amidation of a wide range of functionalized thioamides with aryl-, heteroaryl-, and alkyl-substituted dioxazolones under the Cp*Co -catalyzed conditions. The observed regioselectivity towards primary C(sp )-H activation is supported by computational studies and the cyclometalation is proposed to proceed by means of an external carboxylate-assisted concerted metalation/deprotonation mechanism.

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An in situ generated Pd-Cy*Phine catalyst has been successfully applied to the N-arylation of primary and secondary amines, and it exhibited high performance across multiple substrate classes. The performance induced by the meta-terarylphosphine motif of the Cy*Phine ligand for C-N cross-coupling displayed only subtle differences to that of its biarylphosphine congener XPhos. DFT studies demonstrated comparable reaction energetics in the catalytic cycle steps for both Pd-Cy*Phine and Pd-XPhos, which was consistent with previous findings.

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The first selective, dual sensor for Ca(2+) and Cd(2+) capable of detection at 100 pM concentrations was designed and synthesized. The experimental observations made for the MC-cation complexes and the selectivity of compounds 1 and 2 with Ca(2+) and Cd(2+) ions were further explored using density functional theory. A first step toward a nanoliter-scale dip sensor for the dual sensing of Ca(2+) and Cd(2+) was demonstrated using microstructured optical fiber as the sensing platform which is important for ion sensing in confined spaces such as the medium surrounding cell clusters.

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The structures and energetics of eight substituted bis(thiocarbonyl)disulfides (RCS(2))(2), their associated radicals RCS(2)(*), and their coordination compounds with a lithium cation have been studied at the G3X(MP2) level of theory for R = H, Me, F, Cl, OMe, SMe, NMe(2), and PMe(2). The effects of substituents on the dissociation of (RCS(2))(2) to RCS(2)(*) were analyzed using isodesmic stabilization reactions. Electron-donating groups with an unshared pair of electrons have a pronounced stabilization effect on both (RCS(2))(2) and RCS(2)(*).

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The fluorogenic indicator 2-[6-(4'-amino)phenoxy-3H-xanthen-3-on-9-yl]benzoic acid (APF) is used widely to detect and measure reactive nitrogen and oxygen species such as peroxynitrite, ONOO-, both in vivo and in vitro. We present in this work the results of a combined computational and experimental study to provide insights into the mechanism of the reaction of APF with the radical products of ONOO- reaction with CO2, namely NO2* and CO3*-. The experimental study on the inhibition of APF oxidation by HCO3- suggests that a direct reaction of APF with nitrosoperoxycarbonate, ONOOCO2-, is unlikely.

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The homolytic dissociation of the important vulcanization accelerator tetramethylthiuram disulfide (TMTD) has been studied by ab initio calculations according to the G3X(MP2) and G3X(MP2)-RAD theories. Homolytic cleavage of the SS bond requires a low enthalpy of 150.0 kJ mol-1, whereas 268.

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