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Superatom-assembled boranes,carboranes,and low-dimensional boron nanomaterials based on aromatic icosahedral B_(12)and C_(2)B_(10)

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Nano Research 2024年第7期17卷 6734-6740页

作者： Qiao-Qiao Yan Yan-Fang Wei Qiang Chen Yue-Wen Mu Si-Dian Li institute of molecular Science Shanxi UniversityTaiyuan 030006China

Using the experimentally known aromatic icosahedral superatoms I_(h)B_(12)H_(12)2−and D_(5d)1,12-C_(2)B_(10)H_(12)as building blocks and based on extensive density functional theory calculations,we predict herein a series of core–shell superpolyhedral boranes and carboranes in a bottom-up approach,including the high-symmetry Th B_(12)@B_(152)H_(72)2−(2),C2h C_(2)B_(10)@B_(152)H_(72)(3),D_(3d)B_(12)@B_(144)H_(66)(4),I_(h)B_(12)@C_(24)B_(12)0H_(72)2−(6),and D_(5d)C_(2)B_(10)@C_(24)B_(12)0H_(72)(7).More interestingly,the superatom-assembled linear D2h B_(36)H_(32)^(2−)(8),close-packed planar D_(3d)B_(84)H_(60)^(2−)(10),and nearly close-packed core−shell D_(3d)B_(12)@B144H_(6)6(4)can be extended periodically to form the one-dimensional(1D)α-rhombohedral borane nanowire B_(12)H_(10)(Pmmm)(9),two-dimensional(2D)α-rhombohedral monolayer borophane B_(12)H_(6)(P m1)(11),and the experimentally known three-dimensional(3D)α-rhombohedral boron(R m)(12)which can be viewed as an assembly of the monolayer B_(12)H_(6)(11)staggered in vertical direction,setting up a bottom-up strategy to form low-dimensional boron-based nanomaterials from their borane“seeds”via partial or complete *** bonding analyses indicate that the high stability of these nanostructures originates from the spherical aromaticity of their icosahedral B_(12)or C_(2)B_(10)structural units which possess the universal skeleton electronic configuration of 1S21P61D101F8 following the Wade’s n+1 *** infrared(IR)and Raman spectra of the most-concerned neutral B_(12)@B144H_(6)6(4)and C_(2)B_(10)@C_(24)B_(12)0H_(72)(7)are computationally simulated to facilitate their experimental characterizations.

关键词： superatom-assembling bottom-up approach density functional theory superpolyhedral boranes superpolyhedral carboranes borophanes

Theoretical investigation of excited dipole bound states of alkali-containing diatomic anions

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Chinese Physics B 2024年第5期33卷 389-393页

作者：连艺肖利丹边丽丽徐海峰闫冰 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China

Information about electronic excited states of molecular anions plays an important role in investigating electron attachment and detachment *** we present a high-level theoretical study of the electronic structures of 12 alkali-metal-containing diatomic anions MX-(MX = LiH,LiF,LiCl,NaF,NaCl,NaBr,RbCl,KCl,KBr,RbI,KI and CsI).The equation-of-motion electron-attachment coupled-cluster singles and doubles(EOM-EA-CCSD) method is used to calculate the electron binding energies(EBEs) of 10 electronic excited states of each of the 12 molecule *** addition of different s-/p-/d-type diffusion functions in the basis set,we have identified possible excited dipole bound states(DBSs) of each *** the investigation of EBEs on the 12 MXs with dipole moment(DM) up to 12.1 D,we evaluate the dependence of the number of anionic excited DBSs on molecular *** results indicate that there are at least two or three DBSs of anions with a molecular DM larger than 7 D and a molecule with DM > 10 D can sustain a π-DBS of the *** study has some implications for the excited DBS electronic states of alkali-metal-containing diatomic molecules.

关键词： anions dipole bound states alkali-metal-containing diatomic molecules

Excitation and ionization of OCS molecules in strong UV and NIR laser fields

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Chinese Physics B 2024年第7期33卷 285-291页

作者：师慧军刘洋孙添吕航徐海峰 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China

Rydberg state excitation(RSE) is a highly non-linear physical phenomenon that is induced by the ionization of atoms or molecules in strong femtosecond laser fields. Here we observe that both parent and fragments(S, C, OC) of the triatomic molecule carbonyl sulfide(OCS) can survive strong 800 nm or 400 nm laser fields in high Rydberg states. The dependence of parent and fragment RSE yields on laser intensity and ellipticity is investigated in both laser fields, and the results are compared with those for strong-field ionization. Distinctly different tendencies for laser intensity and ellipticity are observed for fragment RSE compared with the corresponding ions. The mechanisms of RSE and strong-field ionization of OCS molecules in different laser fields are discussed based on the experimental results. Our study sheds some light on the strong-field excitation and ionization of molecules irradiated by femtosecond NIR and UV laser fields.

关键词： Rydberg state excitation strong field carbonyl sulfide ionization

Advances of graphdiyne-supported metal catalysts in thermocatalytic reactions

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Nano Research 2024年第4期17卷 2223-2233页

作者： Jia Yu Yida Yang Yuliang Li Changyan Cao Weiguo Song Beijing National Laboratory for molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of Molecular Nanostructures and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Laboratory for molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of organic solidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Supported metal catalysts are widely used in the modern chemical *** electronic interaction between supports and active components is of great significance for heterogeneous ***(GDY),a new type of carbon allotrope with sp-hybridized carbon atoms,πconjugate structure,and electron transmission capability,is a promising candidate as catalyst *** years have witnessed the rapid progress of GDY-supported metal catalysts for different catalysis *** that most processes in the current chemical industry are thermocatalytic reactions,we herein give an overview about the advances and particular characteristics of GDY-supported catalysts in these *** geometric structure and electronic properties of GDY are first ***,the synthesis methods for GDY-supported metal catalysts and their applications in thermocatalytic reactions are discussed,in which the effect of electronic interaction on catalytic performance is ***,the current challenges and future directions of GDY-supported metal catalysts for thermocatalysis are *** is expected that this review will enrich our understanding of the advances of GDY as a superior support for metal catalysts in thermocatalytic reactions.

关键词： graphdiyne metal catalysts thermocatalytic reactions heterogeneous catalysis

Direct Observation on H-Elimination Enhancement from C_(2)H_(4) through Non-Adiabatic Process by Femtosecond Laser Induced Coulomb Explosion

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Chinese Physics Letters 2024年第5期41卷 17-22页

作者：金无维王春成赵晓戈杨译章任殿相刘泽槿李孝开罗嗣佐丁大军 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China Jilin Provincial Key Laboratory of Applied Atomic and molecular Spectroscopy Jilin UniversityChangchun 130012China

Ethylene, the simplest model of a carbon-carbon double bond system, is pivotal in numerous chemical and biological processes. By employing intense infrared laser pump-probe techniques alongside coincidence measurements, we investigate the ultrafast non-adiabatic dynamics involved in the breakage of carbon-carbon double bonds and hydrogen elimination in dissociation of ethylene. Our study entails analyzing the dynamic kinetic energy release spectra to assess three bond-breaking scenarios, movements of nuclei, and structural changes around the carbon atoms. This allows us to evaluate the relaxation dynamics and characteristics of various dissociative states. Notably, we observe a significant rise in the yield of fragments resulting from C–H bond breakage with the delay time extended, suggesting non-adiabatic coupling through conical intersections from C–C bond breakage as a probable cause.

关键词： pump Femto adiabatic

Effect of sample temperature on femtosecond laser ablation of copper

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Chinese Physics B 2024年第2期33卷 377-385页

作者：党伟杰陈雨桐陈安民金明星 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China Jilin Provincial Key Laboratory of Applied Atomic and molecular Spectroscopy Jilin UniversityChangchun 130012China

We conduct an experimental study supported by theoretical analysis of single laser ablating copper to investigate the interactions between laser and material at different sample temperatures,and predict the changes of ablation morphology and lattice *** investigating the effect of sample temperature on femtosecond laser processing,we conduct experiments on and simulate the thermal behavior of femtosecond laser irradiating copper by using a two-temperature *** simulation results show that both electron peak temperature and the relaxation time needed to reach equilibrium increase as initial sample temperature *** the sample temperature rises from 300 K to 600 K,the maximum lattice temperature of the copper surface increases by about 6500 K under femtosecond laser irradiation,and the ablation depth increases by 20%.The simulated ablation depths follow the same general trend as the experimental *** work provides some theoretical basis and technical support for developing femtosecond laser processing in the field of metal materials.

关键词： femtosecond laser two-temperature model sample temperature ablation depth

Optimization of extreme ultraviolet vortex beam based on high harmonic generation

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Chinese Physics B 2024年第5期33卷 459-464页

作者：肖礴赵逸文程方晶王革文姜威王一琛胡杰梁红静马日 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China College of Science Jilin Institute of Chemical TechnologyJilin 132022China

In high harmonic generation(HHG),Laguerre–Gaussian(LG) beams are used to generate extreme ultraviolet(XUV)vortices with well-defined orbital angular momentum(OAM),which have potential applications in fields such as microscopy and *** experimental study on the HHG driven by vortex and Gaussian beams is conducted in this *** is found that the intensity of vortex harmonics is positively correlated with the laser energy and gas *** structure and intensity distribution of the vortex harmonics exhibit significant dependence on the relative position between the gas jet and the laser *** ring-like structures observed in the vortex harmonics,and the interference of quantum paths provide an explanation for the distinct structural ***,by adjusting the relative position between the jet and laser focus,it is possible to discern the contributions from different quantum *** optimization of the HH vortex field is applicable to the XUV,which opens up a new way for exploiting the potential in optical spin or manipulating electrons by using the photon with tunable orbital angular momentum.

关键词： high harmonic generation phase matching extreme ultraviolet vortex beam quantum path interference

Atomically Substitutional Engineering of Transition Metal Dichalcogenide Layers for Enhancing Tailored Properties and Superior Applications

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Nano-Micro Letters 2024年第5期16卷 248-284页

作者： Zhaosu Liu Si Yin Tee Guijian Guan Ming‑Yong Han institute of molecular Plus Tianjin UniversityTianjin 300072People’s Republic of China institute of Materials Research and Engineering A*STARSingapore 138634Singapore

Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor *** MX2 layers with different metal and/or chalcogen elements have similar structural parameters but varied optoelectronic properties,providing opportunities for atomically substitutional engineering via partial alteration of metal or/and chalcogenide atoms to produce ternary or quaternary *** resulting multinary TMD layers still maintain structural integrity and homogeneity while achieving tunable(opto)electronic properties across a full range of composition with arbitrary ratios of introduced metal or chalcogen to original counterparts(0–100%).Atomic substitution in TMD layers offers new adjustable degrees of freedom for tailoring crystal phase,band alignment/structure,carrier density,and surface reactive activity,enabling novel and promising *** review comprehensively elaborates on atomically substitutional engineering in TMD layers,including theoretical foundations,synthetic strategies,tailored properties,and superior *** emerging type of ternary TMDs,Janus TMDs,is presented specifically to highlight their typical compounds,fabrication methods,and potential ***,opportunities and challenges for further development of multinary TMDs are envisioned to expedite the evolution of this pivotal field.

关键词： Transition metal dichalcogenides Atomic substitution Tailored structure Tunable bandgap Enhanced applications

An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi Liu Xue-Dong Li Liang Cheng Li Liu Beijing National Laboratory for molecular Sciences (BNLMS) CAS Key Laboratory of Molecular Recognition and Function CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements, which provides efficient methods for the preparation of axially chiral compounds. However, developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination process. In this work, we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent enantioselectivity. In addition, the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis acid. This methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%) and excellent central-to-axial chirality conversion(up to 99% conversion percentage). This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： brønsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

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