eV Energy Research Articles

Influence of magnesium oxide on the physical and spectroscopic properties of manganese doped sodium tetra borate glasses

The effect of alkaline earth oxide on sodium tetraborate was analyzed by fabricating a range of glasses depicted by the formula x MgO-(40-x)ZnO-59.5Na2B4O7-0.5MnO2. Basic character was analyzed and confirmed by XRD tests.Decline in density is attributed to the replacement of high molecular mass ZnO by a relatively less molecular mass MgO. The volume enlargement is discussed in terms of increased bond lengths and induced non- bridging oxygen atoms. Parameters like refractive index, reflection loss, molar refractivity, electron polarizability are obtained from existing relations. All these are indirectly depends on density and molar volume and hence their nature. Optical studies revealed indirect kind of transitions in these glasses ranging the values of optical energy gap between 2.913–3.15 eV and Urbach energy (ΔE) 0.342–0.276 eV showing greater stability of glasses.Mn2 +ion in its d5 state revealed a well resolved sextet centered around g"2.032 indicating Mn2+ ions are in octahedral (Oh) environment resulted from jumps between lower doublet energy states. The resonance of g≈ 2.99 and g≈ 4.22 are related to rhombic surroundings of the Mn2+ and jumps between middle kramers doublets. The value of hyperfine split ‘A′ and Δg= (ge-g) are indicative of ionic bonding between Mn2 + ions and oxygens. Zero field splitting parameter ‘D′ decreases from x = 0 to x = 30 mol% and then increased for x = 40 mol%. Magnitude of unpaired spins(N) participating in the resonance and paramagnetic susceptibility(c) are calculated. FTIR and Raman studies are conducted. FTIR spectra revealed the structural changes from BO4 to BO3 by increasing MgO content. From FTIR and Raman studies it is established that MgO is acting as modifier in the given glass composition.

Dislocation Dynamics in Monocrystalline Si near the Melting Point Studied in Situ by X‐Ray Bragg Diffraction Imaging

To study dislocation dynamics in a model sample, an intrinsic float zone (FZ) Si wafer is chosen as seed to initiate directional solidification. During the temperature ramp, a Von Laue diffraction spot is recorded by a camera. It provides time‐resolved information on the evolution of silicon crystalline quality and on the defect nucleation locations and dynamics. With increasing temperature, dislocations are observed to propagate through the seed starting mainly from the sample edges. The effective thermomechanical local stress is estimated as low as (1.2 ± 0.4) × 105 Pa in a thermal gradient of (1.8 ± 0.2) × 102 K m−1. The latter is sufficient to allow dislocation nucleation and motion at temperatures beyond (1523 ± 9) K. Dislocation velocity increases with temperature and reaches a maximum velocity of (3.0 ± 0.5) × 10−4 m s−1 close to the silicon melting point. From the dislocation velocity measurements as a function of temperature, an activation energy of (3.1 ± 0.6) eV is estimated and this value is discussed, along with dynamical interactions between defects and dislocations.

Interface barrier strategy for perovskite solar cells realized by In-situ synthesized polyionic layer

The harmonious coordination between the perovskite and the charge transport layer is the prerequisite for the high efficiency and stability of perovskite solar cells (PSCs). The excellent photoelectric and solution processable SnO2 electron transport material opens the most commercial potential of planar PSCs. However, SnO2 has rich surface activity and photocatalytic properties, which will deteriorate perovskite after absorbing UV light and seriously affect the stability and efficiency of PSCs. Here, the interface barrier strategy is introduced to insert an anchored-then-rinsed lead polystyrene sulfonate (ARPSS-Pb) polyionic layer between SnO2 and perovskite via in-situ synthesis method to construct a new stable interface, which can effectively block the phase transition of perovskite driven by photocatalytic SnO2. In addition, ARPSS-Pb also has the functions of passivating interfacial defects, relaxing interfacial stress and guiding crystallization of perovskite. PSCs based on ARPSS-Pb achieved a power conversion efficiency (PCE) of 22.26%, much higher than 19.60% of the control devices. More importantly, after 1000 h of storage under continuous humidity conditions, up to 96.32% of the initial PCE is maintained. A high open circuit voltage (VOC) as high as 1.190 V has been obtained for ARPSS-Pb based devices. To our best knowledge, this is the highest VOC achieved in the system of perovskite with 1.56 eV energy gap.

Constraints on Cosmic Ray Acceleration Capabilities of Black Holes in X-ray Binaries and Active Galactic Nuclei

Rotating black holes (BHs) are likely the largest energy reservoirs in the Universe as predicted by BH thermodynamics, while cosmic rays (CRs) are the most energetic among particles detected on Earth. Magnetic fields surrounding BHs combined with strong gravity effects, thanks to the spacetime symmetries, turn the BHs into powerful accelerators of charged particles. At the same time, in the age of multi-wavelength and multi-messenger astronomy, BHs and their environments have not yet been probed with CR messengers, despite being observed across most of the electromagnetic spectrum, and neutrino and gravitational waves. In this paper, we probe the acceleration capabilities of BHs in 8 galactic X-ray binaries and 25 local active galactic nuclei (AGNs) within 100 Mpc, based on the ultra-efficient regime of the magnetic Penrose process of a BH energy extraction combined with observational data. We find that the maximum energy of the galactic BHs can reach only up to the knee of the CR spectrum, including supermassive BH Sgr A* at the Galactic Center. On the other hand, for supermassive BHs in AGNs, we find that the mean energy of primary CRs is of the order of 1019 eV. It is therefore likely that local supermassive BHs give sufficient contribution to the ankle—a sharp change in the slope of the cosmic ray spectrum around 1018.6 eV energy. We also discuss the energy losses of primary CRs close to the acceleration zones. In the galactic BH cases, it is likely dominated by synchrotron radiation losses.

Vacancy migration in α-iron investigated using in situ high-voltage electron microscopy

ABSTRACT Modeling the microstructural evolution of irradiated materials requires knowledge of the migration energies of point defects, which results from energetic particle radiation. Herein, we measured the growth rate of self-interstitial atom (SIA) clusters in electron-irradiated α-iron at 275–320 K using in situ high-voltage electron microscopy. To improve the statistical accuracy of the measurement, we used photographic films and video data. This enabled analysis of a considerable amount of data by extracting several SIA clusters and tracking their size growth using image processing techniques. By fitting the temperature-dependent cluster growth rate to the Arrhenius relations derived using rate theory analysis, we obtained vacancy migration energy of eV. The validity of the estimation method was confirmed from the consistency of the dependence of the damage rate on the cluster growth rate using the applied rate theory analysis. We also investigated the possible roles of faster motion of tri-vacancies compared to those of mono- and di-vacancies, as demonstrated by first-principles calculations, on the obtained migration energy using a kinetic analysis model. In addition, the effects of impurities leading to decrease in the cluster growth rate were briefly discussed.

Uncovering temperature-tempted coordination of inclusions within ultra-high-strength-steel via in-situ spectro-microscopy

Despite the common challenge of investigating non-metallic inclusions within ultra-high-strength-steel (UHSS) at sub-micrometer scale via conventional methods, probing nitride inclusions at elevated temperatures is vital for guiding steel’ performance. Herein, an in-situ spectro-microscopic determination using advanced Synchrotron X-ray absorption spectroscopy (XAS) coupled with photoelectron emission microscopy (PEEM) is employed to explore the local structure and electronic properties of selective h-boron nitride (h-BN) containing inclusions (A1 and A2) embedded within steel matrix. While the variation in the relative intensity of π∗/σ∗ excitonic peaks at spatially different locations refers to the polarization and or thickness effects. Several minute features observed in the 192–195 eV energy range show oxygen (O) substituted nitrogen (N) defects (ON,2N,3N), which are more dominant in A2 inclusion. The observed dominance further explains the relatively high intense π∗ peak in A2 due to increased localization. Weak shoulder on the left side of π∗ peak in both room and high-temperature XAS spectra is ascribed to the interaction between h-BN and the local environment, such as Ca-based inclusion or steel matrix. Defects are commonly found in h-BN, and precise identification of the same is vital as they affect the overall physical, chemical, and mechanical properties. Moreover, significant changes in high-temperature B K-edge XAS spectra, such as relative intensity of π∗/σ∗ excitonic peaks at the same location and reduced intensity of defects, suggest the adjusting nature of BN inclusion, complicating their precise prediction and control towards clean steel production.

A polyacetylene based polyelectrolyte via non-catalyst polymerization of 2-ethynylpyridine and 3,4-dimethoxy benzoyl chloride

A new polyacetylene based polyelectrolyte, poly(N-3,4-dimethoxybenzoyl-2-ethynylpyridinium chloride), was synthesized by the direct polymerization of 2-ethynylpyridine and 3,4-dimethoxybenzoyl chloride. The polymerization successfully proceeded without any additional catalyst or initiator to give a high yield of the product. The chemical structure of poly(N-3,4-dimethoxybenzoyl-2-ethynylpyridinium chloride) was confirmed using 1H and 13C nuclear magnetic resonance spectroscopy, as well as Fourier transform infrared spectroscopy. Further, optical properties, electrochemical properties, and thermal stabilities were investigated by cyclic voltammetry, UV-Vis absorption spectra, photoluminescence spectra, thermogravimetric analysis. Comparing UV-Visible absorption and photoluminescence spectrum, the polymer showed the band gap of 2.18 eV and photon energy of 2.58 eV.

Identification of the defect dominating high temperature reverse leakage current in vertical GaN power diodes through deep level transient spectroscopy

Deep level defects in wide bandgap semiconductors, whose response times are in the range of power converter switching times, can have a significant effect on converter efficiency. We use deep level transient spectroscopy (DLTS) to evaluate such defect levels in the n-drift layer of vertical gallium nitride (v-GaN) power diodes with VBD ∼ 1500 V. DLTS reveals three energy levels that are at ∼0.6 eV (highest density), ∼0.27 eV (lowest density), and ∼45 meV (a dopant level) from the conduction band. Dopant extraction from capacitance–voltage measurement tests (C–V) at multiple temperatures enables trap density evaluation, and the ∼0.6 eV trap has a density of 1.2 × 1015 cm−3. The 0.6 eV energy level and its density are similar to a defect that is known to cause current collapse in GaN based surface conducting devices (like high electron mobility transistors). Analysis of reverse bias currents over temperature in the v-GaN diodes indicates a predominant role of the same defect in determining reverse leakage current at high temperatures, reducing switching efficiency.

Novel pathway for the sonochemical synthesis of silver nanoparticles with near-spherical shape and high stability in aqueous media

The present study shows the development of a novel sonochemical synthesis pathway of sub-15 nm silver nanoparticles (AgNPs) with quasi-spherical shape and high stability in aqueous suspension. Different analytical techniques such as on-line UV–Vis spectroscopy, Atomic Force Microscopy (AFM), and Transmission Electron Microscopy (TEM) were complementarily used to characterize the evolution of the properties of AgNPs synthesized with this new route. Furthermore, different centrifugation conditions were studied to establish a practical, simple and straightforward purification method. Particle size was determined by TEM employing two different deposition methods, showing that purified AgNPs have a size of 8.1 nm ± 2.4 nm with a narrow dispersion of the size distribution (95% coverage interval from 3.4 to 13 nm). Critical information of the shape and crystalline structure of these sub-15 nm AgNPs, provided by shape descriptors (circularity and roundness) using TEM and high resolution (HR)-TEM measurements, confirmed the generation of AgNPs with quasi-spherical shapes with certain twin-fault particles promoted by the high energy of the ultrasonic treatment. Elemental analysis by TEM-EDS confirmed the high purity of the sub-15 nm AgNPs, consisting solely of Ag. At the optical level, these AgNPs showed a bandgap energy of (2.795 ± 0.002) eV. Finally, the evaluation of the effects of ultraviolet radiation (UVC: 254 nm and UVA: 365 nm) and storage temperature on the spectral stability revealed high stability of the optical properties and subsequently dimensional properties of sub-15 nm AgNPs in the short-term (600 min) and long-term (24 weeks).

Measurement of Energy Spectrum and Elemental Composition of PeV Cosmic Rays: Open Problems and Prospects

Cosmic rays represent one of the most important energy transformation processes of the universe. They bring information about the surrounding universe, our galaxy, and very probably also the extragalactic space, at least at the highest observed energies. More than one century after their discovery, we have no definitive models yet about the origin, acceleration and propagation processes of the radiation. The main reason is that there are still significant discrepancies among the results obtained by different experiments located at ground level, probably due to unknown systematic uncertainties affecting the measurements. In this document, we will focus on the detection of galactic cosmic rays from ground with air shower arrays up to 1018 eV. The aim of this paper is to discuss the conflicting results in the 1015 eV energy range and the perspectives to clarify the origin of the so-called ‘knee’ in the all-particle energy spectrum, crucial to give a solid basis for models up to the end of the cosmic ray spectrum. We will provide elements useful to understand the basic techniques used in reconstructing primary particle characteristics (energy, mass, and arrival direction) from the ground, and to show why indirect measurements are difficult and results are still conflicting.

Prediction of heptagonal bipyramidal nonacoordination in highly viable [OB-M\xa9B7O7-BO]\u2212 (M\u2009=\u2009Fe, Ru, Os) complexes

Non-spherical distributions of ligand atoms in coordination complexes are generally unfavorable due to higher repulsion than for spherical distributions. To the best of our knowledge, non-spherical heptagonal bipyramidal nonacoordination is hitherto unreported, because of extremely high repulsion among seven equatorial ligand atoms. Herein, we report the computational prediction of such nonacoordination, which is constructed by the synergetic coordination of an equatorial hepta-dentate centripetal ligand (B7O7) and two axial mono-dentate ligands (-BO) in the gear-like mono-anionic complexes [OB-M©B7O7-BO]– (M = Fe, Ru, Os). The high repulsion among seven equatorial ligand B atoms has been compensated by the strong B–O bonding. These complexes are the dynamically stable (up to 1500 K) global energy minima with the HOMO-LUMO gaps of 7.15 to 7.42 eV and first vertical detachment energies of 6.14 to 6.66 eV (being very high for anions), suggesting their high probability for experimental realization in both gas-phase and condensed phases. The high stability stems geometrically from the surrounded outer-shell oxygen atoms and electronically from meeting the 18e rule as well as possessing the σ + π + δ triple aromaticity. Remarkably, the ligand-metal interactions are governed not by the familiar donation and backdonation interactions, but by the electrostatic interactions and electron-sharing bonding.

Rationally regulating the terminal unit and copolymerization spacer of polymerized small-molecule acceptors for all-polymer solar cells with high open-circuit voltage over 1.10 V

Two polymerized small molecule acceptors with wide bandgaps of ∼1.65 eV and high-lying LUMO energy levels above −3.70 eV were designed by introducing a novel terminal unit. Efficient all-PSCs with high VOC over 1.10 V were achieved.

Synthesis and characterization of Mg-doped ZnO thin-films for photovoltaic applications

Zinc oxide (ZnO) has gained significant interest in the last few years due to its attractive properties for the transparent electronics industry, particularly due to its large direct band gap (Eg) ∼ 3.3 eV and exciton binding energy ∼60 meV. In this study, we report the elaboration and characterization of ZnO and Mg-doped ZnO (MZO) thin films with different Mg doping concentrations (0%, 2%, 3%, 4%, 5%, respectively).The Mg-doped ZnO (MZO) thin films were synthesized by the sol–gel immersive method on glass substrates, employing dehydrated zinc acetate, magnesium, ethanol as solvent, and MEA as stabilizer. The impact of Mg doping concentration on the structural and optical properties of the prepared films was examined using X-ray diffraction and UV visible spectroscopy, respectively. The (002) peak of the Mg-doped ZnO thin films is observed to be shifted to a higher angle as a consequence of Mg doping. The transmittance spectra reveal that Mg doping may increase the optical band gap of ZnO thin films. The band gap is adjusted from 2.95 eV to 3.10 eV by varying the Mg doping concentration between 2% and 5%.

Blue-red emitting materials based on a pyrido[2,3-b]pyrazine backbone: design and tuning of the photophysical, aggregation-induced emission, electrochemical and theoretical properties.

Pyrido[2,3-b]pyrazine-based donor–acceptor–donor (D–A–D) molecules were designed by altering donor amines and synthesized using the Buchwald–Hartwig C–N coupling reaction. Further, the tunable opto-electrochemical properties of the dyes were studied in detail. The dye possesses intramolecular charge transfer (ICT) transition (412–485 nm), which marked the D–A architecture and induces a broad range of emissions from blue to red (486–624 nm) in the solution and solid state. Some of the dyes show aggregation-induced emission (AIE) features and formation of nanoparticles in the THF/H2O mixture, as confirmed by DLS and FEG-SEM (of 7) analysis. The AIE characteristics indicate its solid/aggregate-state application in organic electronics. The molecules exhibit high thermal stability, low band gap (1.67–2.36 eV) and comparable HOMO (−5.34 to −5.97 eV) and LUMO (−3.61 to −3.70 eV) energy levels with those of reported ambipolar materials. The relationship between the geometrical structure and optoelectronic properties of the dyes, as well as their twisted molecular conformation and small singlet and triplet excitation energy difference (ΔEST = 0.01–0.23 eV) were analyzed using the DFT/TDDFT method. Thus, potential applications of the dyes are proposed for optoelectronic devices.

Investigation of the excitations of plasmons and surface exciton polaritons in monoclinic gadolinium sesquioxide by electron energy-loss spectroscopy and plasmon spectroscopic imaging.

The monoclinic gadolinium sesquioxide (denoted as m-Gd2O3) with its lower crystal symmetry exhibits larger dielectric permittivity (κ) than the cubic Gd2O3 (denoted as c-Gd2O3). Recently, a few nanometers thick m-Gd2O3 thin film has been successfully epitaxially grown on a GaN substrate as a promising candidate gate oxide in metal-oxide-semiconductor field-effect transistors (MOSFETs). Thus, it is important to understand the electronic excitations in m-Gd2O3 and investigate them by electron energy loss spectroscopy (EELS) performed with aloof electron beams and electron diffraction to gain the spatial and momentum resolutions. In this study, using scanning transmission electron microscopy combined with EELS (STEM-EELS) in the aloof electron beam setup, we observed low-loss spectral features at 13 eV and 14.5 eV at the specimen edge in a grazing incidence and the material interior, which can be interpreted as a surface plasmon (SP) and a volume plasmon (VP), respectively. Surface exciton polaritons (SEPs), which represents surface resonances associated with excitonic onsets above the bandgap, were also observed at about 7, 10.2, and 36 eV energy loss. Their surface excitation character was confirmed by energy-filtered transmission electron microscopy spectrum imaging (EFTEM-SI) and using relativistic energy versus-momentum (E–k) map calculations. The momentum (q)-dependent EELS indicates that the SEP features near the bandgap represented a function of q and revealed a nondispersive behavior for VP and SEP at 36 eV. The oscillator strengths for VP and SEP at 36 eV dropped at different q values along with different q directions, revealing the anisotropic electronic structures of m-Gd2O3.

Vulnerability Assessment for Coupled Network Consisting of Power Grid and EV Traffic Network

With the rapid development of EV in the transportation system, its increasing influence on the power system has attracted more and more attention in recent years. Under such a background, a virtual EV energy network (VEEN) in traffic level coupled with the corresponding power grid is formed in this paper, considering the energy carried by EVs in a specified area as a virtual node. To further identify the vulnerable components in the coupled energy network, a hybrid approach based on a complex network (CN) is presented. A hybrid power transfer distribution factor (HPTDF) is proposed for the coupled energy network considering the variation of VEENs over time. Then, the line betweenness and the modified time-varying coupling net-ability are designed to evaluate the vulnerability of the coupled network. Furthermore, to demonstrate the applicability of the proposed models, three case studies are performed on the 39-bus IEEE power network coupled with a 19-node VEEN. The simulation result verifies the effectiveness of the method in terms of identifying the critical lines in a coupled energy network, and a vulnerability assessment progress by designing a slow-fast dynamic cascade failure simulator in this paper verifies that a VEEN layer coupling defense strategy can decrease the vulnerability of a power grid layer under random attacks.

Luminescence and energy transfer processes in LuNbO4:Bi, Eu

Microcrystalline powders of LuNbO4:Bi3+, Eu3+ with the same nominal Bi3+ concentration (2 at.%) and different nominal Eu3+ concentrations (varying from 0 to 8 at.%) are synthesized and analyzed by the X-ray diffraction method. Photoluminescence characteristics of the co-doped LuNbO4:Bi, Eu powders are investigated by the steady-state and time-resolved luminescence spectroscopy methods in a wide temperature range (4.2–500 K) and compared with those of the undoped and bismuth-doped LuNbO4. It is found that owing to the overlap of the intrinsic and Bi3+-related emission bands with the absorption bands of Eu3+, an effective non-radiative (resonance) energy transfer from both the host and the Bi3+-related exciton-like states to Eu3+ ions, resulting in the appearance of the luminescence in the 1.6–3.8 eV energy range, takes place in LuNbO4:Bi, Eu. The exchange interaction is found to be responsible for the energy transfer process. The possible application of LuNbO4:Bi, Eu in white light-emitting diodes is discussed.

A comparative study of the lattice structure, optical band gap, electrical conductivity and polarization at different stages of the heat treatment of chemical routed Al(OH)3

Aluminium hydroxide (Al(OH)3) was prepared by chemical reaction of the Al(NO3)3 in alkaline medium. The as-prepared powder was heated in the temperature range 250 °C to 1250 °C for studying the structural phase transformation at different stages of the heat treatment. The synchrotron x-ray diffraction patterns confirmed a structural transformation of Al(OH)3 through different (Boehmite, γ, θ, δ, and α) polymorphic phases of Al2O3 on increasing the heat treatment temperature. The samples in Boehmite (γ-AlOOH) and α- Al2O3 phases showed Raman active modes, whereas the intermediate (meta-stable) multi-phased structure showed weak Raman active peaks. The analysis of UV–visible spectra of the samples indicated two optical band gap energy values in the high energy range 4.50–4.73 eV and low energy range 3.06–3.84 eV. The voltage dependence of current, capacitance and electrical polarization were recorded to study electrical properties in heat treated samples. The capacitance value, derived from the polarization, showed a usual increasing trend on decreasing the measurement frequency (inverse of the time) of driving electric voltage. The measured electrical polarization in the samples was found to be highly correlated to their electrical conductivity and the results are helpful to understand the role of electrical conductivity on exhibiting the apparently ferroelectric properties in high conductive and low polarizable dielectric oxides.

Electron Paramagnetic Resonance and Optical Studies of Thermoluminescence Processes in Mn-Doped YAlO3 Single Crystals

A detailed electron paramagnetic resonance (EPR), optical absorption, luminescence, and thermoluminescence (TL) study of Mn-doped YAlO3 (YAP) single crystals was performed. The crystals were grown by the Czochralski method from stoichiometric (Y/Al = 1) and yttrium-rich (Y/Al = 1.04) melts and codoped with either Si or Hf ions. The EPR measurements revealed the presence of only one type of Mn2+ center, that is, isolated Mn ions occupying Y sites (MnY2+). It was found that only in yttrium-rich crystals, the MnY2+ ions undergo recharging to MnY3+ under ionizing irradiation, indicating that this process requires the availability of sufficiently deep electron traps. The initial charge state is fully restored only after subsequent warming above 600 K. The presented results demonstrate, moreover, that MnY3+ + e → MnY2+ recombination is not the most efficient excitation channel of the green 4T1 → 6A1 emission of MnY2+, possibly because of the huge energy difference between the recombination (>5.39 eV) and excitation (3 eV) energies. In contrast, energy transfer to MnY2+ proves to be dominant. A general model of trapping and recombination mechanisms responsible for TL of YAP:Mn crystals above room temperature is proposed. Besides MnY2+ ions and the defect-related electron and hole traps intrinsic to the YAP lattice, the model includes also unintentional dopants such as FeAl2+ acting as deep hole traps, as well as MnAl4+ and CrAl3+ ions acting both as deep hole and electron traps.

Neutral Dissociation of Pyridine Evoked by Irradiation of Ionized Atomic and Molecular Hydrogen Beams.

The interactions of ions with molecules and the determination of their dissociation patterns are challenging endeavors of fundamental importance for theoretical and experimental science. In particular, the investigations on bond-breaking and new bond-forming processes triggered by the ionic impact may shed light on the stellar wind interaction with interstellar media, ionic beam irradiations of the living cells, ion-track nanotechnology, radiation hardness analysis of materials, and focused ion beam etching, deposition, and lithography. Due to its vital role in the natural environment, the pyridine molecule has become the subject of both basic and applied research in recent years. Therefore, dissociation of the gas phase pyridine (C5H5N) into neutral excited atomic and molecular fragments following protons (H+) and dihydrogen cations (H2+) impact has been investigated experimentally in the 5–1000 eV energy range. The collision-induced emission spectroscopy has been exploited to detect luminescence in the wavelength range from 190 to 520 nm at the different kinetic energies of both cations. High-resolution optical fragmentation spectra reveal emission bands due to the CH(A2Δ→X2Πr; B2Σ+→X2Πr; C2Σ+→X2Πr) and CN(B2Σ+→X2Σ+) transitions as well as atomic H and C lines. Their spectral line shapes and qualitative band intensities are examined in detail. The analysis shows that the H2+ irradiation enhances pyridine ring fragmentation and creates various fragments more pronounced than H+ cations. The plausible collisional processes and fragmentation pathways leading to the identified products are discussed and compared with the latest results obtained in cation-induced fragmentation of pyridine.