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CO3

Carbon trioxide (CO₃) is a neutral, metastable oxocarbon molecule composed of one carbon atom and three oxygen atoms, existing primarily as a short-lived intermediate rather than a stable compound under standard conditions.^[1] It decomposes spontaneously into carbon dioxide (CO₂) and atomic oxygen (O), with lifetimes on the order of microseconds in gas phase or longer when isolated in cryogenic matrices.^[2] First identified in 1966 through infrared spectroscopy of species generated from the reaction of carbon monoxide (CO) with ozone (O₃) in argon matrices, CO₃ exhibits multiple isomeric forms, including a C_{2v}-symmetric ground state structure featuring a central carbon doubly bonded to one oxygen and single-bonded to a peroxo-like O-O group, distinct from a higher-energy D_{3h} planar isomer.^[1]^[3] Quantum chemical calculations and spectroscopic studies confirm its electronic structure involves Jahn-Teller distortion in degenerate states, influencing its reactivity and observed spectra.^[4] CO₃ holds significance in atmospheric and interstellar chemistry as a transient species formed via oxygen atom addition to CO₂, potentially contributing to oxidation pathways in planetary atmospheres or cosmic ices, though its instability limits direct observation in natural environments.^[5]^[6] Experimental production methods, such as photolysis or electron impact on CO₂, alongside theoretical modeling, continue to refine understanding of its role in extreme conditions like those in Enceladus-like icy bodies or low-temperature matrices.^[7]^[8]

Chemical Identity and Overview

Definition and Distinction from Carbonate

Carbon trioxide (CO₃) is a neutral oxocarbon, an unstable oxide composed solely of one carbon atom and three oxygen atoms, existing primarily as transient intermediates in low-temperature matrices or gas-phase reactions.^[9]^[10] It features multiple isomeric forms, including cyclic (C_{2v}) and acyclic (D_{3h}) structures, but lacks the thermodynamic stability required for persistence under standard conditions, decomposing readily to carbon dioxide (CO₂) and atomic oxygen (O).^[2] First proposed in theoretical studies during the late 1960s and confirmed experimentally in 1971 through infrared (IR) spectroscopy of matrix-isolated species generated from atomic oxygen reactions with CO₂, CO₃ represents a short-lived reactive species rather than a bulk chemical entity.^[11] In contrast, the carbonate ion (CO₃^{2-}) is a stable polyatomic anion with the same elemental composition but bearing a -2 charge, formed by the deprotonation of carbonic acid (H₂CO₃) and ubiquitous in aqueous solutions, mineral salts such as calcium carbonate (CaCO₃), and biological systems like bicarbonate buffering in blood. While CO₃ as a neutral molecule exhibits high reactivity and fleeting existence—often detectable only via spectroscopic trapping techniques—the carbonate ion's resonance-stabilized structure enables long-term stability in ionic compounds, contributing to geological formations like limestone deposits comprising over 4% of Earth's crust and serving essential roles in carbon cycling.^[10] This fundamental charge difference underlies their divergent behaviors: the neutral CO₃'s tendency toward dissociation precludes its accumulation, whereas CO₃^{2-} forms enduring lattices in solids and equilibria in solutions.^[9]

Molecular Formula and Isomers

The molecular formula of carbon trioxide is CO₃, corresponding to a molecule with one carbon atom and three oxygen atoms, exhibiting radical character due to an unpaired electron.^[12] The primary structural isomers of CO₃ include the C_{2v} (cyclic, dioxirane-like), C_s (asymmetric open-chain), and D_{3h (planar triangular) forms, distinguished by their point group symmetries and bonding arrangements. The C_{2v isomer, the global minimum, features a three-membered ring with a C=O double bond and two adjacent C-O single bonds, yielding optimized bond lengths of 1.173 Å (C=O) and 1.330 Å (C-O) at the CCSD(T)/cc-pVTZ level.^[12]^[13] Its ground electronic state is ²A₂, with characteristic vibrational modes including a CO stretch at 2078 cm⁻¹ (a₁ symmetry) and a bend at 606 cm⁻¹ (a₁ symmetry), computed via CCSD(T)/cc-pVTZ.^[12] The D_{3h isomer adopts a planar triangular geometry with three equivalent C-O bonds of 1.256 Å at the same computational level, though it exhibits an imaginary bending frequency (-402 cm⁻¹, e' symmetry), suggesting marginal instability as a transition state rather than a true minimum.^[12] Relative to the C_{2v ground state, the D_{3h form lies 5.81 kcal/mol higher in energy at CCSD(T)/cc-pVTZ, though higher-order CCSDT corrections reduce this gap to 3.03 kcal/mol; earlier lower-level methods like MP2 erroneously predict the D_{3h as more stable by inverting the order due to overestimated correlation in the degenerate LUMO.^[12] The C_s isomer, featuring an asymmetric open structure (e.g., resembling O=C-O-O), represents a higher-energy local minimum, though specific energetic and geometric parameters from ab initio methods place it above the C_{2v but below certain dissociation limits in variational studies.^[13] These relative stabilities and geometries derive from coupled-cluster methods like CCSD(T), which provide benchmark accuracy for such multireference systems influenced by Jahn-Teller distortions in the D_{3h case, underscoring the C_{2v dominance under equilibrium conditions.^[12]

Physical and Chemical Properties

Stability and Decomposition

CO₃ is highly unstable, characterized by a short lifetime in the gas phase at room temperature, typically on the order of milliseconds to seconds, due to its radical nature and strained bonding.^[2] This instability manifests in spontaneous decomposition without catalysts, as observed in photolysis experiments involving ozone irradiation in liquid CO₂, yielding a quantum efficiency of 0.18 ± 0.03 for CO₃ formation followed by rapid decay.^[2] The dominant decay pathway is the bimolecular disproportionation 2 CO₃ → 2 CO₂ + O₂, governed by second-order kinetics with a rate constant of 2.3 × 10⁹ M⁻¹ s⁻¹ at 298 K.^[2] This process is exothermic (ΔH = -85.6 kcal/mol) and features a low activation barrier of 12.3 kcal/mol, facilitating concerted C–O bond cleavage and O–O bond formation.^[2] The half-life remains under one minute even at -45 °C, underscoring the molecule's intrinsic reactivity.^[2] Stability is enhanced at lower temperatures and in isolated environments; for instance, matrix isolation at 10–20 K permits temporary stabilization for spectroscopic study, though decomposition accelerates with temperature increases that promote radical diffusion and recombination.^[2] Pressure dependence is secondary in dilute systems, where unimolecular pathways are negligible compared to bimolecular decay.^[2]

Spectroscopic Properties

Infrared spectroscopy has been instrumental in identifying and characterizing the isomers of CO3, primarily through matrix isolation techniques. For the cyclic C_{2v} isomer, matrix isolation studies in solid CO2 or Ar report key vibrational bands including the symmetric C=O stretch at 2045 cm^{-1} (strong), O-O stretch at 1073 cm^{-1} (medium), C-O stretch at 972 cm^{-1} (strong), and O-C=O bend at 568 cm^{-1} (medium).^[14] These assignments stem from isotopic substitution experiments confirming the molecular structure. The acyclic D_{3h} isomer exhibits distinct IR features, notably the asymmetric e' C-O stretch at approximately 1165-1167 cm^{-1}, along with bending modes in the 700-800 cm^{-1} region, as observed in neon matrix experiments following vacuum ultraviolet photolysis of CO2.^[15] High-resolution infrared spectra from low-energy ion implantation into CO2 ices at 30-80 K have refined these assignments by detecting both isomers simultaneously, with the cyclic form showing the 2045 cm^{-1} band and the acyclic at 1167 cm^{-1}, alongside production of O3 at 1042 cm^{-1}. Such experiments simulate astrophysical conditions and confirm the persistence of these bands without significant broadening, supporting matrix-isolated data. Early liquid-phase photolysis studies also evidenced CO3 formation, though with less resolved spectra due to solvent interactions.^[16] Ultraviolet absorption spectra of neutral CO3 remain sparsely documented, with limited direct observations attributed to its transient nature, but photodetachment from the CO3^- anion provides indirect insights into electronic transitions. Negative ion photoelectron (NIPE) spectroscopy of CO3^- reveals detachment to the neutral D_{3h} singlet ground state (¹A₁'), with an electron affinity of 4.06 ± 0.03 eV, and a low-energy triplet state (³A₂') separated by approximately 0.2 eV.^[17] The spectrum displays a vibrational progression at 560 cm^{-1}, consistent with Jahn-Teller distortion in the triplet state, and confirms the ²A₂' ground state of the anion, enabling assignment of electronic states like X̃²A₂ and Ã²B₂ through Franck-Condon analysis. These measurements validate the singlet ground state preference for the acyclic isomer over cyclic forms.

Synthesis and Detection

Laboratory Production Methods

Carbon trioxide (CO₃) has been produced in laboratory settings through photolysis of ozone dissolved in liquid carbon dioxide, where ultraviolet irradiation generates atomic oxygen that reacts with CO₂ to form the transient CO₃ species.^[18] This method isolates CO₃ under controlled low-temperature conditions to stabilize the molecule for study.^[18] Ion implantation techniques using low-energy ions on solid carbon dioxide ices at cryogenic temperatures (30 K amorphous or 80 K crystalline) yield CO₃ alongside ozone. Experiments employed reactive ions such as 1.5 keV H⁺ or 2.12 keV D⁺, and non-reactive 3 keV He⁺, with the reactive ions promoting atomic oxygen production that adds to CO₂ frameworks, enhancing CO₃ formation yields compared to non-reactive cases.^[19] The process demonstrates reproducible synthesis in solid-state matrices, with CO₃ growth observed proportional to irradiation dose.^[19] Electron irradiation of CO₂-dominated ices also generates CO₃ through dissociation pathways producing oxygen atoms that insert into CO₂ units, forming the cyclic isomer stable under vacuum up to CO₂ sublimation temperatures near 90 K.^[20] These irradiation methods mimic energetic processing in controlled environments, confirming CO₃ as a key intermediate in oxide chemistry.^[20]

Detection Techniques

Matrix isolation infrared (IR) spectroscopy serves as the principal method for detecting and characterizing the neutral CO₃ molecule, enabling the isolation of short-lived species in noble gas matrices at cryogenic temperatures to obtain high-resolution vibrational spectra. The D₃h isomer of ¹²C¹⁶O₃ was first spectroscopically identified in 2006 through its asymmetric stretch (ν₁) at approximately 1,627 cm⁻¹ and bending mode (ν₂) at 1,028 cm⁻¹, observed following the reaction of oxygen atoms with CO₂ in an argon matrix.^[21]^[22] These assignments were corroborated by quantum chemical computations simulating the IR spectra, which matched the experimental band positions and isotopic shifts.^[23] Mass spectrometry techniques detect the CO₃⁻ radical anion, often generated in gas-phase ion sources or cluster experiments, with its mass-to-charge ratio at m/z 60 confirming identity through fragmentation patterns and ion energetics data.^[24] This approach has been applied to study anion stability and reactions, such as hydration effects, though it primarily probes ionic rather than neutral forms.^[25] Time-resolved absorption and resonance Raman spectroscopy provide insights into CO₃ radical kinetics, capturing transient spectra in solution or gas phase with pulse radiolysis or photolysis initiation. For instance, oxidation of bicarbonate generates CO₃⁻ detectable via UV-Vis absorption near 600 nm, with decay rates measured on microsecond timescales.^[26]^[27] Distinguishing CO₃ signals from interfering species like CO₂ clusters or transient adducts remains challenging due to overlapping spectral regions; isotopic substitution with ¹³C or ¹⁸O induces measurable frequency shifts (e.g., 20-50 cm⁻¹ for ¹⁸O), enabling unambiguous assignment by comparison with predicted patterns from ab initio calculations.^[21] Multiple experimental replicates and complementary computational validation are essential to mitigate matrix effects or photodecomposition artifacts.^[28]

Theoretical and Computational Studies

Electronic Structure

Carbon trioxide (CO₃) possesses 22 valence electrons, leading to distinct electronic configurations in its isomers. The cyclic C₂ᵥ isomer, the lowest-energy form, features bonding akin to a dioxirane structure with a central carbon atom bonded to two oxygen atoms in a three-membered ring and a third oxygen via a double bond. This configuration exhibits peroxide-like O-O bonding, characterized by a weak single bond and significant diradical character in the frontier molecular orbitals, where unpaired electron density resides primarily on the ring oxygens, necessitating multireference treatments for accurate wavefunction description. In contrast, the higher-energy D₃ₕ planar isomer displays a degenerate ground-state occupancy in e' orbitals, resulting in a first-order Jahn-Teller distortion that lowers the symmetry to C₂ᵥ and stabilizes the structure through vibronic coupling.^[29]^[30] High-level ab initio calculations, including coupled-cluster methods like CCSD(T), predict the energy difference between the C₂ᵥ minimum and D₃ₕ transition state to be small, on the order of a few kcal/mol, underscoring the role of dynamic Jahn-Teller effects in the potential energy surface. Bond dissociation energies for key fragmentations, such as C₂ᵥ CO₃ → CO₂ + O(¹D), have been computed at approximately 47 kcal/mol (197 kJ/mol), reflecting the relatively weak peroxide linkage and facilitating facile decomposition pathways. These values align with equation-of-motion coupled-cluster computations that account for electron correlation beyond Hartree-Fock approximations.^[23]^[30] Vertical excitation energies to low-lying states, computed via EOM-CCSD, reveal a dense manifold of singlet and triplet excitations in the near-UV region, with the D₃ₕ isomer showing stronger vibronic interactions due to pseudo-Jahn-Teller couplings among multiple E states. A 2007 computational study integrated these excitations with photoelectron spectral simulations, demonstrating that conical intersections and linear vibronic coupling constants govern the observed progressions in the ν₃ and ν₂ modes, confirming the dominance of dynamic over static distortions in the neutral species. Such analyses highlight the multiconfigurational nature of excited states, where time-dependent density functional theory (TD-DFT) underestimates energies compared to coupled-cluster benchmarks.^[30]^[29]

Potential Energy Surfaces

The potential energy surface (PES) of carbon trioxide (CO₃) features a closed-shell singlet C_{2v} cyclic isomer as the global energy minimum, characterized by a bent structure with significant double-bond character in the C-O linkages. Computational studies employing multi-reference methods, such as complete active space self-consistent field (CASSCF), reveal this minimum's stability, with the PES displaying shallow wells that reflect CO₃'s transient nature. The D_{3h} planar isomer represents a higher-energy local minimum, lying approximately 0.1 kcal/mol above the C_{2v} structure, connected by a low isomerization barrier of about 4.4 kcal/mol, facilitating rapid interconversion under typical conditions.^[31]^[23] Dissociation pathways on the singlet PES favor fragmentation to CO₂ + O(³P) as the lowest-energy route, with the reverse association (O + CO₂ → CO₃) being exothermic by roughly 28-30 kcal/mol, though the forward barrier from the C_{2v} minimum involves a loose transition state or minimal activation due to the molecule's weak binding. Higher barriers, on the order of 20 kcal/mol, appear in constrained paths like bicoordinate dissociation, but the global PES scan confirms the CO₂ + O channel dominates over alternatives such as ring-opening to linear isomers. Triplet surfaces, relevant for spin-forbidden processes, exhibit similar minima but with intersystem crossings enabled by spin-orbit coupling, as refined in post-2007 calculations incorporating relativistic effects for accurate radical state descriptions.^[32] Accurate PES mapping requires multi-reference treatments like CASSCF(16,13) to capture diradical contributions, particularly near the D_{3h} geometry, where single-reference methods overestimate stability. Convergence is achieved with correlation-consistent basis sets such as aug-cc-pVTZ, yielding bond lengths and angles consistent with spectroscopic data (e.g., C-O ~1.43 Å in C_{2v}). These computations highlight the PES's sensitivity to electron correlation, with coupled-cluster refinements confirming the shallow isomerization landscape and low-lying dissociation channels.^[32]^[12]

Occurrence and Astrophysical Relevance

In Atmospheric Chemistry

Carbon trioxide (CO₃) acts as a short-lived intermediate in stratospheric photochemistry, primarily arising from the addition of excited oxygen atoms, O(¹D), to CO₂ molecules abundant in the upper atmosphere.^[33]^[34] This reaction, O(¹D) + CO₂ → CO₃*, occurs following ozone photolysis (O₃ + hν → O(¹D) + O₂), where CO₃* represents an energized complex that typically redissociates into CO₂ and ground-state O(³P) atoms within picoseconds to microseconds, depending on the isomer (e.g., cyclic C₂ᵥ or planar D₃ₕ forms).^[35]^[23] Approximately 2% of O(¹D) atoms form the cyclic CO₃ isomer via insertion into the C=O bond, but collisional stabilization is inefficient at stratospheric pressures (∼10⁻³ to 10⁻⁵ mbar), preventing significant buildup.^[36] The primary fate of stabilized CO₃ involves rapid unimolecular decomposition or bimolecular reaction with atomic oxygen, such as CO₃ + O → CO₂ + O₂, with rate constants on the order of 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ under thermal conditions.^[32] This pathway contributes minimally to O₂ formation or oxygen atom removal compared to dominant O(³P) + O₂ + M → O₃ + M recombination cycles. Kinetic models of stratospheric chemistry, incorporating JPL/NASA reaction rates, predict steady-state CO₃ concentrations below 10⁶ molecules cm⁻³ in the 30–50 km altitude range, orders of magnitude lower than key radicals like OH or Cl, due to its instability and lack of persistent production sources beyond O(¹D) quenching.^[35]^[32] Empirical assessments from balloon-borne and satellite measurements of stratospheric CO₂ isotope ratios (e.g., Δ¹⁷O enrichment) indirectly validate CO₃'s role in atom exchange during O(¹D) + CO₂ encounters but show no evidence of CO₃-driven perturbations to ozone profiles or loss rates.^[35] Comprehensive photochemical models, such as those simulating Antarctic ozone depletion, attribute <0.1% of odd-oxygen loss to CO₃-involved paths, far overshadowed by halogen catalysis; similarly, its transient nature precludes any measurable greenhouse forcing, as radiative lifetimes exceed chemical ones by factors of 10⁶ or more.^[33]^[34] Laboratory simulations of stratospheric conditions—using low-pressure flow tubes, crossed atomic beams, and matrix isolation at 10–77 K—reproduce CO₃ formation yields of 1–5% from O + CO₂ and confirm decomposition half-lives under 1 ms at 200–300 K, with no detectable accumulation even in CO₂-rich mixtures.^[23]^[36] These experiments, aligned with quantum chemical calculations of potential energy surfaces, underscore CO₃'s confinement to minor, local roles in O(¹D) deactivation rather than sustained atmospheric processing.^[32]

In Interstellar Medium and Planetary Atmospheres

Carbon trioxide (CO₃) is predicted to arise in the interstellar medium through the irradiation of CO₂-rich ices by ultraviolet photons or cosmic rays, processes mimicking conditions in dense molecular clouds.^[37] Laboratory experiments replicating these environments, such as vacuum ultraviolet photolysis of pure CO₂ ice at temperatures below 20 K, yield CO₃ as a prominent product, identifiable via infrared bands near 12.5 μm corresponding to its ν₃ asymmetric stretching mode. Such formation pathways suggest CO₃ could contribute to the chemical complexity of interstellar grain mantles, though its metastability limits persistence.^[37] Despite extensive infrared and millimeter-wave surveys of interstellar sources, CO₃ has not been detected, implying fractional abundances relative to CO₂ on the order of less than 10⁻³ or lower in typical ice compositions.^[38] This contrasts sharply with the ubiquity of CO and CO₂, which exhibit column densities exceeding 10¹⁶ cm⁻² in many clouds, highlighting CO₃'s role as a short-lived intermediate rather than a reservoir species.^[38] In planetary atmospheres, CO₃ acts as a transient intermediate in oxygen isotope exchange mechanisms, notably facilitating the preferential enrichment of ¹⁸O in CO₂ on Mars, where photochemical reactions involving atomic oxygen and CO₂ produce the cyclic C₂ᵥ isomer.^[36] Models of Martian upper atmospheric chemistry, incorporating rate constants for O + CO₂ → CO₃ derived from low-temperature matrix studies, indicate steady-state concentrations below 10⁻¹⁰ of total CO₂, evading direct spectroscopic confirmation by missions like MAVEN.^[39] No confirmed detections exist in other solar system atmospheres, such as those of Venus or outer planet satellites, underscoring CO₃'s elusive nature beyond laboratory and theoretical contexts.^[38]

Higher Oxocarbons

CO₃ exemplifies the higher oxocarbons within the COn series (n=3–8), where monomeric forms serve as transient intermediates or precursors to extended polymeric carbon oxide structures under compression. These species exhibit structural analogies to CO₃, such as cyclic isomers (e.g., C₂ᵥ-symmetric rings in CO₄) or fused ring motifs in higher n, contrasting with the linear stability of CO and CO₂.^[40] Empirical synthesis of CO₄ and CO₅ mirrors that of CO₃, relying on matrix isolation at cryogenic temperatures (typically 4–20 K) via oxygen atom reactions with CO₂ or UV photolysis of precursors like CO₂/O₂ mixtures, enabling spectroscopic characterization before thermal decomposition. For instance, the C₂ᵥ isomer of CO₄ was detected by infrared spectroscopy following O + CO₃ addition, while the C₂-symmetric CO₅ isomer emerged from similar O-atom accretion pathways. Stability decreases with n: CO₃ persists metastably in matrices but dissociates rapidly to CO₂ + O upon warming (half-life ~1 s at 30 K), rendering it less robust than CO₂ yet observable under isolation, unlike fleeting higher analogs that require even lower temperatures for detection. In contrast to the more persistent carbon suboxide (C₃O₂), which distills at –7 °C and polymerizes slowly above –30 °C, CO₃ demands matrix confinement for study due to its exothermic decomposition barrier of ~30 kcal/mol.^[41]^[42]^[8] Under gigapascal pressures, higher oxocarbons like CO₃ contribute to CO₂ polymerization, forming amorphous phases with embedded CO₃-like trigonal units amid tetrahedral carbon linkages, as simulated in mantle-relevant compositions (e.g., pyrolite + CO₂ at >50 GPa). These transformations, observed experimentally above 40–60 GPa and 1000–2000 K, yield extended networks akin to "carbonia" but incorporating mixed-valence C–O motifs from metastable monomers. Computational surveys through 2025 highlight cyclic COₙ (n≥5) favoring single-ring geometries over fused variants, underscoring their role as building blocks in high-pressure carbon chemistry.^[43]^[44]

Reactions with Other Species

The reactivity of carbon trioxide (CO₃) is dominated by its role as a transient intermediate, with unimolecular decomposition to CO and O₂ representing the principal pathway, consistent with microscopic reversibility of the O + CO₂ association reaction.^[45] Computational investigations employing ab initio-derived potential energy surfaces and energy-grained master equation analyses have characterized the kinetics of this decomposition across singlet and triplet states for temperatures from 1000 to 5000 K, revealing temperature-dependent branching ratios and phenomenological rate constants that align with prior experimental data on the forward association.^[45] In low-temperature matrix isolation experiments, the higher-energy D₃ₕ isomer of CO₃ displays a slow destruction rate of 1.8 × 10⁻⁴ s⁻¹, attributed to statistical ejection of oxygen atoms following energy redistribution, with an isomerization barrier of 18.4 kJ mol⁻¹ from the more stable C₂ᵥ form. Bimolecular decay channels, while potentially dominant under higher-density conditions, lack extensive direct measurement; no stable adducts with common species are known, and predicted additions to radicals (e.g., CO₃ + H leading to fragmented products such as HOCO + O) remain computationally inferred without empirical confirmation of rate constants or mechanisms. Empirical evidence from irradiated CO₂/O mixtures demonstrates CO₃-mediated production of CO and O₂ upon photolysis or annealing, underscoring its instability and reversion to dissociation products without persistent secondary species. Although proposed as a combustion intermediate facilitating oxygen atom quenching or isotope exchange, such roles await verification through direct spectroscopic detection or kinetic modeling under relevant conditions.^[45] Transition state theory-based barriers for dissociation, derived from potential energy surface scans, support rapid unimolecular lifetimes in gas-phase environments, contrasting matrix-stabilized persistence.^[45]

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Identification of the D3h Isomer of Carbon Trioxide (CO3) and Its ...
Aug 6, 2025 · 3 The D 3h isomer of CO 3 was first identified by Jamieson et al. in 2006 using infrared spectroscopy. 4 They suggested that this structure in ...
[40]
[PDF] On the formation of higher carbon oxides in extreme environments
These experi- ments presented explicit evidence that, a cyclic carbon trioxide molecule (CO3) is stable in low-temperature matrices. In addition to this ...
[41]
Novel detection of the C 2v isomer of carbon tetraoxide (CO 4 )
Here, we report on the first spectroscopic detection of the cyclic (C2v) isomer of carbon tetraoxide (12C16O4) via its ν1 vibrational mode centered around 1941 ...
[42]
First detection of the C 2 symmetric isomer of carbon pentaoxide ...
Jul 27, 2007 · These higher order carbon oxides have been theoretically predicted to be stable, however, their detection has been difficult.Missing: COn | Show results with:COn
[43]
Carbon chemistry and polymerization. a Relative abundance of CO2 ...
Carbon chemistry and polymerization. a Relative abundance of CO2, CO3, and CO4 as a function of pressure for pyrolite + 5.16 wt% CO2 (4CO2 units per cell) ...
[44]
[PDF] Exploring the diversity of molecular carbon oxides, and ... - USPEX
Feb 6, 2025 · They discovered that for molecules with m ≥ 5 it is more favorable to form one cycle rather than 2 fused cycles, which agrees with our results.
[45]
https://doi.org/10.1021/acs.jpca.5c00242

CO3