Types Of Carbon Atoms Research Articles

Carbon Nanoparticle Oxidation by NO2and O2: Chemical Kinetics andReaction Pathways.

Carbon nanoparticle interactions with gases are central to many environmental and technical processes, but the underlying reaction kinetics and mechanisms are not well understood. Here, we investigate the oxidation and gasification of carbon nanoparticles by NO2and O2under combustion exhaust conditions. We build on a comprehensive experimental data set and use a kinetic multilayer model (KM-GAP-CARBON) to trace the uptake and release of gas molecules alongside the temporal evolution of particle size and surface composition. The experimental results are captured by a model mechanism that involves different types of carbon atoms (edge/plane-like) and the formation of a reactive oxygen intermediate (activated CO complex) as the rate-limiting step. A transition between distinct chemical regimes driven by NO2at lower temperatures and O2at higher temperatures is reflected by an increase in the observable activation energy from ~60 kJ/mol to ~130 kJ/mol. We derive energy profiles for three alternative reaction pathways that involve uni- or bimolecular decomposition of reactive oxygen intermediates.

Carbon Nanoparticle Oxidation by NO2 and O2: Chemical Kinetics and Reaction Pathways

Carbon nanoparticle interactions with gases are central to many environmental and technical processes, but the underlying reaction kinetics and mechanisms are not well understood. Here, we investigate the oxidation and gasification of carbon nanoparticles by NO2 and O2 under combustion exhaust conditions. We build on a comprehensive experimental data set and use a kinetic multilayer model (KM‐GAP‐CARBON) to trace the uptake and release of gas molecules alongside the temporal evolution of particle size and surface composition. The experimental results are captured by a model mechanism that involves different types of carbon atoms (edge/plane‐like) and the formation of a reactive oxygen intermediate (activated CO complex) as the rate‐limiting step. A transition between distinct chemical regimes driven by NO2 at lower temperatures and O2 at higher temperatures is reflected by an increase in the observable activation energy from ~60 kJ/mol to ~130 kJ/mol. We derive energy profiles for three alternative reaction pathways that involve uni‐ or bimolecular decomposition of reactive oxygen intermediates.

Kinetic Computation of Cyclization Reactions of Large Keto-Hydroperoxide Radicals in Low Temperature Combustion.

The cyclization reactions of keto-hydroperoxide (KHP) radicals leading to the formation of keto cyclic ethers and OH radicals play an important role in low temperature combustion for hydrocarbon fuels or oxygenated hydrocarbon fuels. However, due to the lack of kinetic data of cyclization reactions of KHP radicals, researchers often derive high-pressure-limit rate constants of cyclization reactions of KHP radicals from analogous cyclization reactions of hydroperoxyl alkyl radicals during construction of the combustion mechanism. This study aims to systematically investigate the kinetics of cyclization reactions of KHP radicals involving short-to-large-sized radicals. The studied reactions are divided into 7 reaction classes, according to the size of the cyclic transition state, the conjugative effect (whether KHP radicals are resonance-stabilized or not), and the position of the carbonyl group (whether the carbonyl group is inside or outside of the reaction center). The isodesmic reaction method, in conjunction with transition state theory, is utilized for each reaction class to compute the energy barriers and high-pressure-limit rate constants at the DFT level. The study revealed that energy barriers calculated at the DFT level with correction by the isodesmic reaction method are close to the results from the benchmark CCSD(T) method. To develop more accurate rate rules, these reaction classes are further divided into subclasses based on the relative site of the OOH group with the carbonyl group, the type of carbon atoms where the OOH group is located, and the type of carbon atoms where the radical site is located. For each subclass, high-pressure-limit rate rules are derived by averaging the rate constants of reactions in the subclass, and it is found that the maximum absolute deviation of the energy barrier and the ratio of the largest rate constant to the smallest rate constant among reactions in each subclass are within chemical accuracy limits, indicating acceptable use of the developed rate rules. A comparison of the rate constants for cyclization reactions of KHP radicals with the values of analogous cyclization reactions of hydroperoxyalkyl radicals as provided in reported mechanisms is made. Additionally, a comparison is drawn between our developed rate rules for subclasses of the cyclization reactions of KHP radicals and the rate rules for analogous subclasses of cyclization reactions of hydroperoxyl alkyl radicals. These comparisons demonstrate significant differences and highlight the necessity for improved rate rules for cyclization reactions of KHP radicals to enhance the automatically generated combustion mechanisms for hydrocarbon and oxygenated hydrocarbon fuels.

Theoretical characterization of the adsorption configuration of pyrrole on Si(100) surface by x-ray spectroscopy

The possible configurations of pyrrole absorbed on a Si(100) surface have been investigated by x-ray photoelectron spectroscopy (XPS) and near-edge x-ray absorption fine structure (NEXAFS) spectra. The C-1s XPS and NEXAFS spectra of these adsorption configurations have been calculated by using the density functional theory (DFT) method and full-core hole (FCH) approximation to investigate the relationship between the adsorption configurations and the spectra. The result shows that the XPS and NEXAFS spectra are structurally dependent on the configurations of pyrrole absorbed on the Si(100) surface. Compared with the XPS, the NEXAFS spectra are relatively sensitive to the adsorption configurations and can accurately identify them. The NEXAFS decomposition spectra produced by non-equivalent carbon atoms have also been calculated and show that the spectral features vary with the diverse types of carbon atoms and their structural environments.

Development of a new force field for the family of primary aliphatic amines using the three steps systematic parameterization procedure

The applicability of the three steps systematic parametrization procedure (3SSPP) to develop a force field for primary amines was evaluated in the present work. Previous simulations of primary amines show that current force fields (FF) can underestimate some experimental values under room conditions. Therefore, we propose a new set of parameters, for an united atom (UA) model, that can be used for short and long amines which predict correctly thermodynamic and dynamical properties. Following the 3SSPP methodology, the partial charges are chosen to match the experimental dielectric constant whereas the Lennard-Jones (LJ) parameters, ε and σ, are fitted to reproduce the surface tension at the vapor-liquid interface and the liquid density, respectively. Simulations were initially conducted for the propylamine molecule by introducing three different types of carbon atoms, Cα and Cβ, with electric charges, and Cn, without charge. Then, modifying the charges of the carbons and using the transferable LJ parameters, the new set of constants for long amines were found. The results show good agreement for the experimental dielectric constant and mass density with a percentage error less than 1% surface tension the error is up to 4% ethylamine, the new charges were obtained from a fitting function calculated from the long amines results. For these molecules, the values of the dielectric constant and the surface tension present errors of the order of 10% with the experimental data. Miscibility of the amines was also tested with the new parameters and the results show reasonable agreement with experiments.

In English

The hexagon-shape graphene nanoflakes (GNFs) limited by zigzag edges only (with doubly and triply coordinated atoms) have unique increased reactivity. Despite the high systems symmetry (D6h) the Carbon atoms in GNFs occupy non-equivalent positions. Can such physical and chemical characteristics of GNFs, which depend of the atom position in the cluster, definition? This characteristic together with the simplicity of its calculation makes it possible to predict the properties of nanoflakes obtained from GNFs by introducing single and multiatomic vacancies into them or by replacing Carbon atoms with electron withdrawing and electron donating atoms. This characteristic includes the C1s core-level binding energy shifts, the maxima of which characterize the C atoms of a certain type. The proposed work is devoted to quantum chemical calculations of the electronic density of states (DOS) of pristine hexagon-shape GNF C96 (multiplicity, M=5), their saturated counterpart –polycyclic aromatic hydrocarbon(PAH) C96H24 (M=1) and their derivatives with one and two single vacancies in the ground electronic state (GES). All calculations were performed using the density functional theory (DFT) method with the involvement of the valence-split basis set 6-31G (d,p). Systems with open shells were considered using the UB3LYP exchange-correlation functional. The obtained spectra were fitted using Gaussian curve fitting program to determine the binding energy for each peak. The Gaussian function distribution of the theoretically calculated C1s core-level binding energy shifts of GNFs testified the presence of six peaks, each of which refers to a certain type of Carbon atoms. The C1s peak with the highest binding energy (-285.57 eV) is caused by contributions from the doubly coordinated edge cyclic chain (ECC) Carbon atoms. The C1s orbitals of the central hexagon (CHex) atoms and the first cyclic chain (FCC) atoms form delocalized molecular orbitals (MOs) in different parts of the cluster. The analogous spectrum of PAH C96H24 is slightly shifted to the region of lower binding energies and contains only two well-defined peaks. The peak with a higher binding energy (-284.36 eV) is generated by the 1s states of the CHex atoms and the atoms of the FCC, which are bounded to the CHex atoms. The electronic DOS difference in C1s core-level spectra of GNF C96 (M=5) and their saturated counterpart PAH C96H24 is established due to the presence of two weakly bounded π-systems in GNF and common conjugated system in PAH. The electronic DOS of defect-containing cluster C96-1(1) (M=3) (one CHex atom has been removed from the C96nanoflake) is generated by the C1s core-level atoms of the second cyclic chain (SCC), which are located at the different distances from the center of the nanoflake. The peak of the lowest intensity (-284.63 eV) appears in the spectrum as a reflection of the appearance of doubly coordinated Carbon atoms surrounding the single vacancy in the C96-1(1) nanoflake. The analysis of the electronic DOS of the C1s core-level spectrum of the C96-2(1) nanoflakeis shown, that doubly coordinated Carbon atoms, concentrated around two single vacancies, are essentially non-equivalent. If the MO with the lowest binding energy is localized on two of them – the MO with the highest binding energy is localized on the third atoms (one around each single vacancy). The electronic C1s core-level DOS spectrum of defect-containing molecular systems with one C96-1(1)H24 and two C96‑2(1)H24 single vacancies are similar to the analogous spectrum of PAH C96H24. In the first of them – one additional maximum appears due to C1s atoms surrounding the single vacancy. In the second – there are two additional maxima, each of which is generated by C1s core-level atoms adjacent to individual vacancies.

Heteroatom-doped fullerene C70 as non-metal electrocatalysts for oxygen reduction and oxygen evolution from computational study

Here, we report on computational oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) efficiencies of a series of heteroatom-doped fullerene C70 (X(Cn), with B, N, O or Si as dopant X, replacing five different types of carbon atoms (Cn, n = 1–5) on C70). It is clarified that the X(Cn) is thermodynamically stable. ΔG⁎OH shows a good linear relationship with ΔG⁎OOH and ΔG⁎O. It is worth noting that the ORR overpotential values of N(C1), N(C2), N(C3) and N(C4) are 0.87 V, 0.75 V, 0.67 V and 0.73 V, respectively, which are all greater than Pt (ηORR = 0.45 V), but it shows that ORR can still be catalyzed. Compared with the pristine C70, both B and N doping can reduce OER overpotential value and improve OER performance. In particular, N(C4) (ηOER = 0.55 V) has the closest overpotential to traditional noble metal OER catalysts such as RuO2 (ηOER = 0.42 V), indicating that it can be used as a potential candidate for OER catalysts. According to the volcano plots, the best ORR and OER activities of X(Cn) appear at ΔG⁎OH = 0.56 eV and ΔG⁎O − ΔG⁎OH = 1.78 eV, respectively. This work can provide some clues for the design and discovery of new non-metal carbon-based electrocatalysts.

Topological Indices of Derived Networks of Benzene Ring Embedded in P -Type Surface on 2 D

Topological index (TI) is a numerical number assigned to the molecular structure that is used for correlation analysis in pharmacology, toxicology, and theoretical and environmental chemistry. Benzene ring embedded in the P -type surface on 2 D network has stability similar to C 60 and can be defined as 3 D linkage of C 8 rings. This structure is the simplest possible tilling of the periodic minimal surface P which contains one type of carbon atom. In this paper, we compute general Randić, general Zagreb, general sum-connectivity, first Zagreb, second Zagreb, and A B C and G A indices of two operations (simple medial and stellation) of 2 D network of benzene ring. Also, the exact expressions of A B C 4 and G A 5 indices of these structures are computed.

ANALISIS MISKONSEPSI PESERTA DIDIK KELAS XII MENGGUNAKAN TES DIAGNOSTIK THREE-TIER MULTIPLE CHOICE PADA MATERI HIDROKARBON

This study aims to identify misconceptions experienced by students in class XII in MAN A and SMAN B in Cirebon City on hydrocarbon material. The research method used is quantitative descriptive method. The sampling technique or subjects used cluster random sampling technique, where the subjects in this study were students of Class XII MIPA 2 in MAN A of the Cirebon City and XII Science 1 in SMAN B of the Cirebon City with the number of students from two schools as many as 45 people. The instrument used is the Three-Tier Multiple Choice Diagnostic Test by categorizing the understanding of concepts possessed by students. The category is divided into three, namely, understanding the concept, not understanding the concept and misconception. The results showed that students in MAN A of the Cirebon City and SMAN B of Cirebon City experienced the highest misconception in the sub-material types of carbon atoms and hydroxide compounds. While the lowest misconception is in the sub-material grouping of hydrocarbon compounds in both schools. The causes of misconceptions of students due to associative thinking, humanistic thinking, incomplete reasoning, students' interest and motivation to learn, abstract chemical concepts, teachers do not optimize learning strategies. Keywords: Misconceptions, Three-Tier Diagnostic Tests, Hydrocarbons

NMR study of dyadic and triadic splitting in copoly(arylene)phthalides based on diphenyl oxide and diphenyl sulfide.

All 13 C NMR signals of the poly(arylene) polymers, O-1, S-7, OS-4, OOS-3, OOOS-2, SSO-5, and SSSO-6 (where O is a diphenyleneoxiphthalide unit and S is a diphenylenethiophthalide unit) in dyads and triads were assigned unequivocally with two-dimensional NMR techniques (ge-2D [1 H-1 H] COSY, ge-2D [1 H-13 C] HSQC, and ge-2D [1 H-13 C] HMBC), and for each atom, the increments of the shifts are determined. For structurally similar carbon atoms of the phthalide cycle and heteroaromatic fragments of the skeletal chain, additive signal splitting schemes in phthalide centered dyads and in diphenylene oxide and in diphenylene sulfide centered triads are considered, based on taking into account the contributions to their shielding of adjacent and distant substituents. It was shown that the nature of the splitting of the signals of each of the 20 carbon atoms in 3,3-bisphenylphthalide fragments is determined by the type of carbon atom (tertiary or quaternary, even or odd), the type of heteroatoms in adjacent heteroaromatic fragments, their distance from the identified carbon nucleus, and their polyad symmetry. The results obtained in this article will greatly facilitate our further studies and, in particular, will allow us to study the microstructure of statistical copolymers based on the asymmetric OS monomer at the dyad and triad levels.

Electronic Energy Relaxation in a Photoexcited Fully Fused Edge-Sharing Carbon Nanobelt.

Carbon nanobelts are cylindrical molecules composed of fully fused edge-sharing arene rings. Because of their aesthetically appealing structures, they acquire unusual optoelectronic properties that are potentially suitable for a range of applications in nanoelectronics and photonics. Nevertheless, the very limited success of their synthesis has led to their photophysical properties remaining largely unknown. Compared to that of carbon nanorings (arenes linked by single bonds), the strong structural rigidity of nanobelts prevents significant deformations away from the original high-symmetry conformation and, therefore, impacts their photophysical properties. Herein, we study the photoinduced dynamics of a successfully synthesized belt segment of (6,6)CNT (carbon nanotube). Modeling this process with nonadiabatic excited state molecular dynamics simulations uncovers the critical role played by the changes in excited state wave function localization on the different types of carbon atoms. This allows a detailed description of the excited state dynamics and spatial exciton evolution throughout the nanobelt scaffold. Our results provide detailed information about the excited state electronic properties and internal conversion rates that is potentially useful for designing nanobelts for nanoelectronic and photonic applications.

Pyrolysis mechanisms of graphene oxide revealed by ReaxFF molecular dynamics simulation

Pyrolysis dynamics of graphene oxide (GO) is critical for composite material design, and a few experimental evaluations were conducted so far since extremely high temperature condition is needed. In this work, with help of ReaxFF reactive molecular dynamics simulations, the pyrolysis mechanisms of GO were investigated from two aspects: (1) the structural evolutions of the carbon skeleton and (2) the desorption of the superficial functional groups. At low temperature, desorption of functional groups is dominant, and little point defects or vacancies are introduced to the carbon skeleton. Meanwhile, generation of a number of pyrolysis products was confirmed at higher temperatures. Accordingly, the carbon skeleton is significantly disordered, resulting in an amorphous transformation. Analysis of bonds breaking ratio, hybridization types of carbon atoms and pyrolytic fragments indicated that the restored sp2-hybridized carbons increase with the increasing annealing time, and structure of final products are controlled by hydroxyl and oxygen dangling bonds. Finally, annealing process of GO with different oxygenal group density (R) and OH/O ratio are quantitatively analyzed and found pyrolysis is R and OH/O ratio dependent. These results uncover the pivotal role of oxygen and hydrogen in pyrolysis, and provide a guidance for heat resistant composite designs.

Regulating the Behavior of Human Gingival Fibroblasts by sp2 Domains in Reduced Graphene Oxide

Long-term function of dental implants relies on not only stable osseointegration but also strong soft tissue-sealing ability. Ideal soft tissue sealing around implants is an effective protective barrier between the external environment and alveolar bone, preventing the invasion of bacteria that is considered as a vital trigger of irreversible marginal bone loss. Carbon-based materials have been reported to be beneficial to soft tissue sealing, which can be regulated through the hybridization type of carbon atoms (sp2 or sp3), but its internal mechanism is still not clear. In this work, graphene oxide with both sp2- and sp3-hybridized carbons was electrophoretic deposited on titanium and reduced to regulate the hybridization type of carbon atoms to investigate its effect and possible mechanism on human gingival fibroblasts (HGFs). X-ray photoelectron spectroscopy and Raman mapping test show the increase of sp2 domain content and the decrease of their size after reduction. Through computer simulation, the possible mechanism of the decrease of sp2 domain size was proposed. In vitro studies disclose that the HGFs exhibit higher proliferation rate, better adhesion, and migration ability with the increase of sp2 domains and the decrease of their sizes. It may be due to the amount and size of sp2 domains that synergistically regulate the amount and properties of adsorbed proteins, thereby influencing the cellular behaviors of HGFs. Our results may offer a different perspective on material designing and academic research to enhance the soft tissue integration of implants.

Reaction Mechanisms and Kinetics of the Hydrogen Abstraction Reactions of C₄⁻C₆ Alkenes with Hydroxyl Radical: A Theoretical Exploration.

The reaction of alkenes with hydroxyl (OH) radical is of great importance to atmospheric and combustion chemistry. This work used a combined ab initio/transition state theory (TST) method to study the reaction mechanisms and kinetics for hydrogen abstraction reactions by OH radical on C4–C6 alkenes. The elementary abstraction reactions involved were divided into 10 reaction classes depending upon the type of carbon atoms in the reaction center. Geometry optimization was performed by using DFT M06-2X functional with the 6-311+G(d,p) basis set. The energies were computed at the high-level CCSD(T)/CBS level of theory. Linear correlation for the computed reaction barriers and enthalpies between M06-2X/6-311+G(d,p) and CCSD(T)/CBS methods were found. It was shown that the C=C double bond in long alkenes not only affected the related allylic reaction site, but also exhibited a large influence on the reaction sites nearby the allylic site due to steric effects. TST in conjunction with tunneling effects were employed to determine high-pressure limit rate constants of these abstraction reactions and the computed overall rate constants were compared with the available literature data.

Progress and Prospects of Graphdiyne‐Based Materials in Biomedical Applications

Graphdiyne is a new member of the family of carbon-based nanomaterials that possess two types of carbon atoms, sp- and sp2 -hybridized carbon atoms. As a novel 2D carbon-based nanomaterial with unique planar structure, such as uniformly distributed nanopores and large conjugated structure, graphdiyne has shown many fascinating properties in mechanics, electronics, and optics since it was first experimentally synthesized in 2010. Up to now, graphdiyne and its derivatives have been reported to be successfully applied in many areas, such as catalysis, energy, environment, and biomedicine, due to these excellent properties. Herein, the current research progress of graphdiyne-based materials in biomedical fields is summarized, including biosensing, biological protection, cancer therapy, tissue engineering, etc. The advantages of graphdiyne and its derivatives are presented and compared with other carbon-based materials. Considering the potential biomedical and clinical applications of graphdiyne-based materials, the toxicity and biocompatibility are also discussed based on current studies. Finally, future perspectives and possible biomedical applications of graphdiyne-based materials are also discussed.

Electronic structures and spectral characteristics of the six C32 fullerene isomers.

In this paper, the six C32 isomers which were of crucial importance in the manufacture of new electronic components were identified by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS). For the discernment, geometry optimizations of the six isomers have been carried out, and the C1s XPS and NEXAFS spectra have been simulated in the frame of density functional theory (DFT). XPS spectra, as accurately reflection of different chemical environments where a particular element was located, provided an effective way to identify the six isomers of C32. The NEXAFS spectra, which were commonly used in the electronic structure detection, captured information of unoccupied orbital and showed many recognizable characteristics. To further investigate the source of spectral features, the spectral components calculated from different types of carbon atoms in each C32 isomer also have been well explored and discussed.

Tailoring π-Conjugated Systems: From π-π Stacking to High-Rate-Performance Organic Cathodes

Summary Organic sodium-ion batteries (OSIBs) have numerous promising advantages for foreseeable large-scale applications, particularly including the convenience of performance optimization through molecular design. However, the reported organic cathodes still suffer from limited capacity, low cyclability, and poor rate performance. The tailoring of the π-conjugated system reported here can enhance the π-π intermolecular interactions, leading to insolubility, long-range layer-by-layer π-π stacking, fast-charge transport, and extraordinary stability and ionic conductivity (10−9 cm2 s−1). Consequently, the obtained cathodes delivered high electrochemical performance with high capacity (∼290 mAh g−1), superior fast-charge-discharge ability (∼160 and 100 mAh g−1 at 10 and 50 A g−1, respectively), and ultra-long cycle life (capacity as high as 97 mAh g−1 after 10,000 cycles at 50 A g−1).

Potential Energy Surface for Large Barrierless Reaction Systems: Application to the Kinetic Calculations of the Dissociation of Alkanes and the Reverse Recombination Reactions.

The isodesmic reaction method is applied to calculate the potential energy surface (PES) along the reaction coordinates and the rate constants of the barrierless reactions for unimolecular dissociation reactions of alkanes to form two alkyl radicals and their reverse recombination reactions. The reaction class is divided into 10 subclasses depending upon the type of carbon atoms in the reaction centers. A correction scheme based on isodesmic reaction theory is proposed to correct the PESs at UB3LYP/6-31+G(d,p) level. To validate the accuracy of this scheme, a comparison of the PESs at B3LYP level and the corrected PESs with the PESs at CASPT2/aug-cc-pVTZ level is performed for 13 representative reactions, and it is found that the deviations of the PESs at B3LYP level are up to 35.18 kcal/mol and are reduced to within 2 kcal/mol after correction, indicating that the PESs for barrierless reactions in a subclass can be calculated meaningfully accurately at a low level of ab initio method using our correction scheme. High-pressure limit rate constants and pressure dependent rate constants of these reactions are calculated based on their corrected PESs and the results show the pressure dependence of the rate constants cannot be ignored, especially at high temperatures. Furthermore, the impact of molecular size on the pressure-dependent rate constants of decomposition reactions of alkanes and their reverse reactions has been studied. The present work provides an effective method to generate meaningfully accurate PESs for large molecular system.

Charge polarization in partially lithiated single-walled carbon nanotubes.

Investigation of carbon/lithium interfaces is of great importance for elaboration of energy storage devices. Here, the effect of vacuum thermal deposition of lithium on single-walled carbon nanotubes (SWCNTs) is investigated by in situ X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure spectroscopy. From the XPS data, the composition of lithiated sample is LiC24. That corresponds to the presence of two types of carbon atoms on the SWCNT surface, namely, those located closely and far away from the adsorbed lithium. Quantum-chemical modeling of XPS valence-band spectra and calculation of atomic charges and molecular electrostatic potential map found that the former type of carbon atoms is in strong positive electric field created by lithium, whereas the Li-free SWCNT areas are charged negatively. An alternation of areas of positive potential and negative potential on the surface of partially lithiated SWCNTs can significantly affect processes in an electrochemical cell.

The effects of diamond amorphous layer on the diamond lapping surface

The diamond presents its versatile applications in chemical, electrical, optical, mechanical and thermal field. Until now, mechanical polishing is the efficient and low-cost technology to shape the diamond to the desired geometry. However, the defects, or amorphization, of the diamond surface is inevitable during the lapping process. This amorphization layer has some adverse effects on the application of diamond. In this paper, the effects of diamond amorphous layer on the diamond lapping surface integrity are studied. By molecular dynamics (MD) simulation method, it is investigated that a diamond sample covered with an amorphous layer is scratched by a diamond abrasive particle. The formed amorphous layer on the diamond lapping surface is analyzed in terms of the distribution of different types of carbon atoms and surface stress. Our work gives an atomic insight into the integrity of the diamond surface with amorphous layer, based on which our understanding on the diamond lapping surface is deepened.