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A new class of yellow- to red-emitting carbazolylgold(III) complexes containing isomeric thienopyridine or thienoquinoline moieties in the cyclometalating ligand has been designed and synthesized, which showed high photoluminescence quantum yields of over 80% in solid-state thin films. The isomeric effect and extended π-conjugation of the N-heterocycles have been found to remarkably perturb the photophysical, electrochemical and electroluminescence properties of the gold(III) complexes. In particular, the operational lifetimes of organic light-emitting devices based on that incorporated with thieno[2,3-c]pyridine are almost three orders of magnitude longer than that incorporated with thieno[3,2-c]pyridine. This has led to long device operational stability with a LT70 value of up to 63 200 h at a luminance of 100 cd m−2 and a long half-lifetime of 206 800 h, as well as maximum external quantum efficiencies of up to 8.6% and 14.5% in the solution-processed and vacuum-deposited devices, respectively. This work provides insights into the development of robust and highly luminescent gold(III) complexes and the identification of stable molecular motifs for designing efficient emitters.

A cationic water-soluble dipicolylamine (DPA)-containing alkynylplatinum(II) terpyridine complex has been synthesized and employed as a dual-selective probe for the detection of cations and anions. The complex was shown to exhibit a strong binding affinity toward Zn2+, whereas the zinc-bound adduct was found to demonstrate the capability of recognizing pyrophosphate (PPi). As evidenced by molecular modeling and various spectroscopic and spectrometric studies, including HR-ESI mass spectrometry, NMR spectroscopy, PXRD measurements, and UV-vis absorption and emission spectroscopy, a PPi anion was found to be capable of bridging two zinc-bound complex molecules in a clip-shaped fashion, which was further oligomerized through intermolecular Pt···Pt and π-π stacking interactions to form nanofibers with a hexagonal columnar phase. This work provides important insights into not only the construction of aesthetically pleasing supramolecular architectures but also the multifunctional probes, which offer great promise to the fields of biosensing and chemical sensing.

A series of photochromic triethylene glycol (TEG)-containing spiropyrans (SPs) has been designed and synthesized. UV–Vis absorption and emission studies demonstrated that their photophysical and photochromic properties can be modulated by varying the linker group between the TEG and the SP components. TEG-containing SPs in THF–water mixtures were found to undergo solvent-induced ring-opening reactions without the need for photoirradiation, which could be attributed to the stabilization of the merocyanine (MC) form in polar solvents. Counterintuitively, a much slower thermal bleaching process of the open MC form has been observed in non-polar solvent media, possibly due to the stabilization of the zwitterionic open form through supramolecular self-assembly. Furthermore, the formation of spherical aggregates resulting from the planarized open MC form has been revealed by dynamic light scattering (DLS), transmission electron microscopy (TEM) and atomic force microscopy (AFM) measurements. Such rational molecular designs, together with the tuning of the solvent polarity and controlled UV light irradiation, have led to the self-assembly of this class of TEG-containing spiropyran derivatives, achieving the systematic and controlled formation of self-assembled functional materials.

A new class of sky-blue- to green-emitting carbazolylgold(III) C^C^N complexes containing pyrazole or benzimidazole moieties has been successfully designed and synthesized. Through the judicious choice of the N-heterocycles in the cyclometalating ligand and the tailor-made carbazole moieties, maximum photoluminescence quantum yields of 0.52 and 0.39 have been realized in the green- and sky-blue-emitting complexes, respectively. Solution-processed and vacuum-deposited organic light-emitting devices (OLEDs) based on the benzimidazole-containing complexes have been prepared. The sky-blue-emitting device shows an emission peaking at 484 nm with a narrow full-width at half-maximum of 57 nm (2244 cm-1 ), demonstrating the potential of this class of complexes in the application of OLEDs with high color purity. In addition, high maximum external quantum efficiencies of 12.3 % and a long operational half-lifetime of over 5300 h at 100 cd m-2 have been achieved in the vacuum-deposited green-emitting devices.

A series of arylgold(III) complexes of tridentate diphenylpyridine ligand incorporated with fluorene and its heterocyclic spiro derivatives, spiro[fluorene-9,9'-xanthene] and spiro[acridine-9,9'-fluorene], as auxiliary ligands has been prepared. This class of complexes exhibits high decomposition temperatures of up to 387 °C, excellent film morphologies in solid-state thin films with a root-mean-square roughness smaller than 0.20 nm, as well as high photoluminescence quantum yields of up to 0.72 in solid-state thin films. Solution-processed organic light-emitting devices (OLEDs) fabricated from this series of complexes as dopants show intense electroluminescence in the sky-blue region with maximum external quantum efficiencies of 10.0%. Taking advantage of their high thermal stability, vacuum-deposited OLEDs have also been fabricated and satisfactory operational lifetimes of ∼300 h have been recorded.

A new class of amphiphilic spiropyran derivatives has been designed and synthesized. Their photophysical and photochromic properties have been investigated. Under UV light irradiation, the ring-closed hydrophobic spiropyrans have been shown to undergo photoinduced ring-opening to give the zwitterionic ring-opened merocyanine forms, which resulted in the amphiphilic properties of the compounds. These compounds were also found to display self-assembly behavior with the formation of H-aggregation in organic solvents under UV irradiation to give different morphologies with diverse nano-structures, leading to promising candidates for the design of a new class of small-molecule photo-responsive materials. The H-aggregate formation has been further supported by computational studies and noncovalent interaction (NCI) analysis of the dimer of the merocyanine form. This represents the first demonstration of the use of NCI analysis on the role played by noncovalent interactions in H-aggregate formation of the spiropyran derivatives.

A simple one-pot two bond-forming reaction for the rapid construction of cyclometalated gold(III) complexes with fully π-conjugated tetradentate ligand is reported. The coupling of the bifunctional gold(III) precursor with the bifunctional aromatic compound has led to the formation of two regioisomers with either C- or N-coordination. Through monitoring by high-throughput high performance liquid chromatography, the regioselectivity of the reaction has been effectively tuned toward the formation of a single isomer, allowing easy separation of the metal complexes. The structures of the complexes have been determined by X-ray crystallography, and the photophysical, electrochemical, and electroluminescence (EL) studies have been carried out. Computational study has been performed to provide insights into the nature of the excited states. Isomeric effect has been shown to have a significant influence on the EL behavior of the organic light-emitting devices.

A new class of four-coordinate donor-acceptor fluoroboron-containing thermally activated delayed fluorescence (TADF) compounds bearing a tridentate 2,2'-(pyridine-2,6-diyl)diphenolate (dppy) ligand has been successfully designed and synthesized. Upon varying the donor moieties from carbazole to 10H-spiro[acridine-9,9'-fluorene] to 9,9-dimethyl-9,10-dihydroacridine, these boron derivatives exhibit a wide range of emission colors spanning from blue to yellow with a large spectral shift of 2746 cm-1 , with high PLQYs of up to 96 % in the doped thin film. Notably, vacuum-deposited organic light-emitting devices (OLEDs) made with these boron compounds demonstrate high performances with the best current efficiencies of 55.7 cd A-1 , power efficiencies of 58.4 lm W-1 and external quantum efficiencies of 18.0 %. More importantly, long operational stabilities of the green-emitting OLEDs based on 2 with half-lifetimes of up to 12 733 hours at an initial luminance of 100 cd m-2 have been realized. This work represents for the first time the design and synthesis of tridentate dppy-chelating four-coordinate boron TADF compounds for long operational stabilities, suggesting great promises for the development of stable boron-containing TADF emitters.

The rational design of a new class of photoresponsive tris(8-hydroxyquinolinato)aluminum(III) (Alq3) complexes has been developed. By incorporating the photochromic dithienylethene units with different peripheral heterocycles into the Alq3 framework, the photochromic properties as well as photoswitching efficiency can be readily modulated, through effective photocyclization of the Al(III) complex. Such intrinsic photochromic behavior leads to the unprecedented enhancement in the electron-transporting properties as demonstrated by the as-fabricated electron-only device, rendering the realization of photoswitchable electron mobility. In addition, one of these complexes is capable of serving as an active layer for solution-processable resistive memory devices. Photocontrollable memory performance has been achieved with a binary memory behavior, with high ON/OFF ratio and long retention time. This work represents not only the first example of photoresponsive Alq3-based electron-transporting materials but also the solution-processable Alq3-based optical and resistive memory devices with photocontrollable performance.

The side-by-side assembly of gold nanorods (GNRs) was shown to be directed by the supramolecular scaffolds formed by sulfonate-containing alkynylplatium(II) terpyridine complexes. Driven by Pt⋅⋅⋅Pt and π-π stacking interactions, the PtII complex has a high propensity to assemble in water with the head-to-tail stacking arrangement to construct supramolecular scaffolds, in which the sulfonate groups on the terpyridine ligand at the peripheral position preferentially bind to the sides of the GNRs. The extent of the assembly of the GNRs into ladder rung-like nanostructures can be modulated by the concentration of the PtII complex. The Pt⋅⋅⋅Pt interaction-assisted formation of the scaffolds and its directed assembly of GNRs were characterized by UV/Vis spectroscopy, quantum-chemical modeling, electron microscopy, energy dispersed X-ray (EDX) analysis, and SERS. This work provides insights for the construction of higher-ordered nano-assemblies using both Pt⋅⋅⋅Pt interactions and template-directed approaches.

A series of bipyridine platinum(II) complexes with different sizes of triangular metallacycles and alkyl/oligoether chains has been synthesized and characterized. They are packed in a zig-zag fashion with the formation of dimeric structures according to their X-ray crystal structures. Different emission origins are observed due to the different sizes of the triangular ligands. Their morphologies could be tuned by the modification of the molecular structures with different metallacyclic alkynyl ligands and alkyl/oligoether chains and solvents. More interestingly, unusual electronic absorption changes and upfield shifts of the aromatic proton resonances are observed upon increasing the temperature, suggesting further aggregation of the architectures. Near-infrared (NIR) emission is also realized through the tuning of the π-π stacking, Pt⋅⋅⋅Pt interactions, and the packing of planar metallacycles.

Various rhodium(I) pincer complexes with different structural features have been prepared and found to display interesting self-assembly properties due to the extensive Rh(I)···Rh(I) interactions. The incorporation of electron-withdrawing −CF3 substituent has been found to improve the stability of the complexes and also facilitate the directed assembly of complex molecules, providing an opportunity for the systematic investigation of the various noncovalent interactions in their versatile self-assembly behaviors and insights into the structure–property relationship in governing the intermolecular interactions. An isodesmic growth mechanism is identified for the solvent-induced aggregation process. The complex molecules exhibit intense low-energy absorption bands corresponding to the absorptions of the dimers, trimers, and higher order oligomers upon aggregation, with energies related to the electronic properties of the tridentate N-donor ligand. Chiral auxiliaries have also been introduced into the rhodiu...

A new class of fused heterocyclic tridentate ligand-containing alkynylgold(III) complexes with tunable emission color has been successfully designed and synthesized. Structural modification of the σ-donating fused heterocyclic alkynyl ligands, including substituted fluorene, carbazole, and triphenylamine, enables a large spectral shift of about 110 nm (ca. 3310 cm-1 ) that covers the green to red region to be realized with the same tridentate ligand-containing alkynylgold(III) complexes in solid-state thin films. Interestingly, the energy of the excimeric emission can be controlled by the rational design of the fused heterocyclic alkynyl ligands. Superior solution-processable organic light-emitting devices (OLEDs) with high external quantum efficiencies (EQEs) of 12.2, 13.5, 9.3, and 5.2 % were obtained with green, yellow, orange, and red emission. These high EQE values are comparable to those of the vacuum-deposited OLEDs based on structurally related alkynylgold(III) complexes.

A series of novel photochromic thieno[3,2-b]phosphole oxides has been shown to demonstrate photochromism without the need for the use of high-energy ultraviolet (UV) light irradiation while maintaining promising photochromic properties such as excellent thermal irreversibility, robust fatigue resistance, and high photoswitching efficiency. Promising visible light-induced photochromic properties have been realized by the new molecular design, in which various π systems have been incorporated into the weakly aromatic phosphole backbone instead of the conventional modification of the peripheral diaryl units that usually leads to a drastic reduction of the photochromic quantum yields (ϕO→C and ϕC→O < 0.01) or even a loss of the photochromic behavior. Excellent fatigue resistance has been observed for a representative compound with no apparent loss of photochromic reactivity over ten photochromic cycles by alternate irradiation with violet (ca. 410 nm) and green (ca. 500 nm) light with high photochromic quantu...

A series of 8-hydroxyquinoline-containing alkynylrhenium(I) tricarbonyl diimine complexes has been designed and synthesized. Their UV-vis absorption, emission as well as electrochemical properties have been studied. Computational studies have also been performed to provide insights into the electronic transitions, excited state origins and electrochemical properties of the complexes.

Dinuclear alkynylplatinum(II) metallofoldamers with an oligomeric m-phenyleneethynylene backbone have been designed with the incorporation of a sterically undemanding, π-conjugated, and hydrophobic 2,6-bis(N-dodecylbenzimidazol-2′-yl)pyridine pincer ligand. The complex with the optimal chain length has been found to exhibit gelation behavior via stabilization by noncovalent Pt···Pt and π–π stacking interactions in the hierarchical architecture constructed from the single-turn helix. The chain lengths of the complexes have been found to be a critical determinant for their gelation behavior, conformations, and morphologies. Such a gelation process has been found to undergo a cooperative assembly mechanism according to the nucleation–elongation model. Their self-assembly via the Pt···Pt and π–π stacking interactions has been studied by 1H NMR, 2D ROESY NMR (ROESY = rotating-frame Overhauser spectroscopy), electronic absorption, and emission spectroscopy, and density functional theory calculations have provid...

Two new axially or peripherally functionalized subphthalocyanines with the decoration of donor–acceptor substituents have been successfully synthesized, characterized and employed in the application of resistive memory device via solution-processable technique. Axially substituted subphthalocyanine shows ternary resistive memory behavior with well-separated current ratios of 1:106:108 between “OFF”, “ON1” and “ON2” states, while only binary logic is observed for peripherally substituted subphthalocyanine. Computational studies show the presence of two well-separated charge transfer states in the axially substituted subphthalocyanine, while the charge transfer processes between the peripheral substituents and the subphthalocyanine core are found to be very close in energy. This work has demonstrated the impact of the substituent positioning on the subphthalocyanine-based memory device performance, providing a new research dimension for the future design and development of multistate organic resistive memory.

A BODIPY-based fluorescent sensor PS with an NO4S2 podand ligand was studied for the selective detection of Pt2+ over 21 cations as well as selected platinum drugs in aqueous medium. The platinum sensor PS shows 28-fold, 22-fold and 14-fold fluorescence turn-on enhancements to Pt2+, cisplatin and nedaplatin, and was thereby employed to detect platinum drugs in A-549 human lung cancer cells.

A new class of pyrazine-based carbazole-containing gold(III) complexes featuring thermally stimulated delayed phosphorescence (TSDP) properties has been designed and synthesized. The emission colors are found to be sensitive to the coordinating atom of the carbazolyl ligands at the gold(III) center, with emission energies spanning from green to red. The efficiency of TSDP can be enhanced by lowering the polarity of the solvent, as supported by the variable-temperature emission and computational studies. Interestingly, a significant spectral shift in electroluminescence with the change of Commission Internationale de L'Eclairage (CIE) coordinates from (0.35, 0.60) to (0.44, 0.54) has been achieved by simply changing the host material from CBP to TmPyPB. Solution-processable organic light-emitting devices (OLEDs) have also been fabricated, with maximum current efficiencies of up to 22.4 cd A-1 and maximum external quantum efficiencies (EQEs) approaching 7.0%. A higher current efficiency of 35.1 cd A-1 and EQE of 10.7% can be achieved for the vacuum-deposited device based on 1, representing the first demonstration of pyrazine-based tridentate ligand-containing gold(III) complexes as phosphorescent material for OLED application.

The Cl + HCOOH reaction is important in the atmosphere, as the chlorine (Cl) atom is an important oxidant, especially in the marine boundary layer, and formic acid (HCOOH) is one of the most abundant organic acids in the troposphere. The reaction surfaces of the two H abstraction channels were computed by second-order unrestricted Møller–Plesset perturbation theory (UMP2) and density functional theory (DFT) calculations. Relative electronic energies were improved to the RCCSD(T)/CBS and UCCSD(T)-F12/CBS levels. The barrier of the C–H hydrogen abstraction channel was found to be lower by about 10 kcal mol−1. Rate coefficients (k) of this channel were calculated at different temperatures at various variational transition state theory (VTST) levels including tunnelling. For single-level direct dynamics VTST calculations, the computed k (2.5 × 10−13 cm3 molecule−1 s−1) using the BMK (Boese and Martin meta hybrid) functional at the highest level (ICVT/SCT) agrees the best with experimental values at 298 K (1.8 and 2.0 × 10−13 cm3 molecule−1 s−1). For dual-level direct dynamics calculations (RCCSD(T)/CBS//MP2 MEP), an adjusted barrier height of 3.1 kcal mol−1 is required to match the ICVT/SCT k with the experimental values. The computed rate coefficients of the Cl + HCOOH reaction is reported for the first time with a temperature range of 200–1500 K. The implications of the results obtained to atmospheric chemistry are discussed.

A series of novel benzo[b]phosphole alkynylgold(I) complexes has been demonstrated to display photochromic and mechanochromic properties upon applying the respective stimuli of light and mechanical force. Promising multistimuli-responsive properties of this series of gold(I) complexes have been successfully achieved through judicious molecular design, which involves incorporation of the photochromic dithienylethene-containing benzo[b]phosphole into the triphenylamine-containing arylethynyl ligand that is susceptible to mechanical force-induced color changes via gold(I) complexation. With excellent thermal irreversibility and robust fatigue resistance of this series of gold(I) complexes, multicolor states controlled by the photochromism and mechanochromism have been realized. Repeatable photochromic and mechanochromic cycles without apparent loss of reactivity have also been observed under ambient conditions. The present work provides important insight and an alternative strategy for the molecular design of multistimuli-responsive materials, paving the way for further development of the underexplored photoresponsive gold(I) complexes and the multistate photocontrolled system.

A theoretical study, involving the calculation of reaction enthalpies and activation energies, mechanisms and rate coefficients, has been made of the reaction of hydroxyl radicals with methyl nitrate, an important process for methyl nitrate removal in the earth's atmosphere. Four reaction channels were considered:- formation of H2O + CH2ONO2, CH3OOH + NO2, CH3OH + NO3, and CH3O + HNO3 . For all channels, geometry optimization and frequency calculations were carried out at the M06-2X/6-31+G** level, while relative energies were improved at the UCCSD(T*)-F12/CBS level. The major channel is found to be the H abstraction channel, to give the products H2O + CH2ONO2. The reaction enthalpy (ΔH298KRX) of this channel is computed as -17.90 kcal.mol-1. Although the other reaction channels are also exothermic, their reaction barriers are high (> 24 kcal.mol-1) and therefore these reactions do not contribute to the overall rate coefficient in the temperature range considered (200-400 K). Pathways via three transition states have been identified for the H abstraction channel. Rate coefficients were calculated for these pathways at various levels of variational transition state theory (VTST) including tunneling. The results obtained are used to distinguish between two sets of experimental rate coefficients, measured in the temperature range 200-400K, one of which is approximately an order of magnitude greater than the other. This comparison, as well as the temperature dependence of the computed rate coefficients, shows that the lower experimental values are favoured. The implications of the results to atmospheric chemistry are discussed.

A series of luminescent cyclometalated N^C^N [N^C^N = 1,3-bis(N-alkylbenzimidazol-2'-yl)benzene]platinum(II) alkynyl and carbazolyl complexes has been prepared. The structure of one platinum(II) carbazolyl complex has been characterized by X-ray crystallography. The corresponding electrochemical and photophysical properties have been explored and analyzed. The N^C^N platinum(II) complexes displayed rich luminescence in degassed dichloromethane solution, with their emission profiles dependent on the coordinated alkynyl and carbazolyl ligands. Their emission energies are correlated to the electronic properties of the alkynyl and carbazolyl ligands. By varying the electronic properties of the alkynyl and carbazolyl ligands, emission energies could be fine-tuned to cover a wide range of the visible spectrum, as supported by computational studies. A donor-acceptor platinum(II) complex has been utilized to fabricate memory devices that exhibit binary memory performances with low operating voltages, high ON/OFF ratios, and long retention times. Solution-processable OLEDs have been fabricated based on another platinum(II) carbazolyl complex, resulting in a maximum external quantum efficiency of up to 7.2%, which is comparable to that of the vacuum-deposited devices based on the small-molecule counterpart, illustrating the multifunctional nature of the platinum(II)-containing materials.

A new class of highly luminescent bipolar alkynylplatinum(II) complexes has been synthesized, characterized, and applied as phosphorescent dopants in the fabrication of solution-processable organic light-emitting devices (OLEDs). Through the incorporation of a delicate balance of electron-donating carbazole moieties and electron-accepting phenylbenzimidazole or oxadiazole moieties into the platinum(II) core, the platinum(II) complexes have been demonstrated to exhibit bipolar charge transport character with high photoluminescence quantum yields of up to 0.75 in thin films. The introduction of meta-linkages into the complexes further helps weaken the donor–acceptor interactions, facilitating better carrier-transporting abilities. More importantly, high-performance solution-processable green-emitting OLEDs with maximum current efficiencies of up to 57.4 cd A–1 and external quantum efficiencies of up to 16.0% have been realized. This is among the best performances for solution-processable phosphorescent OLED...

A theoretical investigation has been carried out on the reaction mechanism and kinetics of the thermal decomposition of hexafluoropropylene oxide (HFPO), a compound of importance in fluorocarbon thin film preparation in the electronics industry. Decomposition occurs via two pathways, 1(a) to give CF2 and CF3C(O)F and 1(b) to give CF2O and CF3CF. Rate coefficients calculated for reaction 1(a) are reported over the temperature range 300–1500 K and compared with the small number of available rate coefficients at selected temperatures within this range. Rate coefficients are reported for the first time for reaction 1(b) over the temperature range 300–1500 K. The geometries of the stationary points on the potential energy surfaces have been obtained at the MP2/6-311++G(d,p) level, and the energies of selected points along the minimum energy path (MEP) have been improved at the RCCSD(T)/AVDZ and RCCSD(T)/AVTZ levels. These improved energies were extrapolated to the complete basis set limit to obtain RCCSD(T)/CBS//MP2/6-311++G(d,p) energies at each selected point on the MEP. The energies were then used in a dual-level direct dynamics method to calculate rate coefficients of the two decomposition reactions. The variational effect on the rate coefficients obtained is found to be small over the whole temperature range and tunnelling plays a small but significant role only at the lower temperatures. Comparison has been made of the computed reaction enthalpies, forward activation energies and rate coefficients computed at the RCCSD(T)/CBS//MP2/6-311++G(d,p) level with those computed with a number of different functionals and with the MP2 method. Reaction 1(a) is found to be the dominant reaction throughout the temperature range considered. Calculated rate coefficients for reaction 1(a) at the highest level used (improved canonical variational theory (ICVT) with small curvature tunnelling (SCT) with the RCCSD(T)/CBS//MP2/6-311++G(d,p) MEP) show reasonably good agreement with two recent sets of experimental values, although agreement with an older set is poor. This comparison highlights the need for more experimental rate coefficients for this thermolysis reaction over the whole temperature range considered, but particularly in the ranges 550–800 K and 1200–1500 K not currently covered by experimental measurements.

Over the last two decades it has emerged that measured hydroxyl radical levels in the upper troposphere are often underestimated by models, leading to the assertion that there are missing sources. Here we report laboratory studies of the kinetics and products of the reaction between CH3O2 and BrO radicals that shows that this could be an important new source of hydroxyl radicals:BrO + CH3O2 → products (1). The temperature dependent value in Arrhenius form of k(T) is k1 = (2.42–0.72+1.02) × 10–14 exp[(1617 ± 94)/T] cm3 molecule–1 s–1. In addition, CH2OO and HOBr are believed to be the major products. Global model results suggest that the decomposition of H2COO to form OH could lead to an enhancement in OH of up to 20% in mid-latitudes in the upper troposphere and in the lower stratosphere enhancements in OH of 2–9% are inferred from model integrations. In addition, reaction 1 aids conversion of BrO to HOBr and slows polar ozone loss in the lower stratosphere.

The reaction between atomic chlorine (Cl) and methyl nitrate (CH3ONO2) is significant in the atmosphere, as Cl is a key oxidant, especially in the marine boundary layer, and alkyl nitrates are important nitrogen-containing organic compounds, which are temporary reservoirs of the reactive nitrogen oxides NO, NO2 and NO3 (NOx). Four reaction channels HCl + CH2ONO2, CH3OCl + NO2, CH3Cl + NO3 and CH3O + ClNO2 were considered. The major channel is found to be the H abstraction channel, to give the products HCl + CH2ONO2. For all channels, geometry optimization and frequency calculations were carried out at the M06-2X/6-31+G** level, while relative electronic energies were improved to the UCCSD(T*)-F12/CBS level. The reaction barrier (Image ID:c4cp06007e-t1.gif) and reaction enthalpy (?HRX298K) of the H abstraction channel were computed to be 0.61 and ?2.30 kcal mol?1, respectively, at the UCCSD(T*)-F12/CBS//M06-2X/6-31+G** level. Reaction barriers (Image ID:c4cp06007e-t2.gif) for the other channels are more positive and these pathways do not contribute to the overall reaction rate coefficient in the temperature range considered (200–400 K). Rate coefficients were calculated for the H-abstraction channel at various levels of variational transition state theory (VTST) including tunnelling. Recommended ICVT/SCT rate coefficients in the temperature range 200–400 K are presented for the first time for this reaction. The values obtained in the 200–300 K region are particularly important as they will be valuable for atmospheric modelling calculations involving reactions with methyl nitrate. The implications of the results to atmospheric chemistry are discussed. Also, the enthalpies of formation, ?Hf,298K, of CH3ONO2 and CH2ONO2 were computed to be ?29.7 and 19.3 kcal mol?1, respectively, at the UCCSD(T*)-F12/CBS level.