Yi Luo

Name: 罗毅; Yi Luo

Organization: The University of Science and Technology of China

Department: Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, and Synergetic Innovation Center of Quantum Information & Quantum Physics

Title: Professor

Chemicals
References

Retrieving the Rate of Reverse Intersystem Crossing from Ultrafast Spectroscopy

Co-reporter:Qun Zhang;Jiahua Hu

The Journal of Physical Chemistry Letters October 6, 2016 Volume 7(Issue 19) pp:3908-3912

Publication Date(Web):September 20, 2016

DOI:10.1021/acs.jpclett.6b01903

Among various nonradiative photophysical processes related to energy migration in singlet–triplet coupled molecular systems, unlike such processes as internal conversion, intersystem crossing (ISC), and intramolecular vibrational relaxation that have been extensively addressed, the reverse ISC (rISC) is a unique one that apparently lacks sufficient interrogation probably owing to its intrinsically elusive nature. In particular, it still remains a nontrivial task to quantitatively describe the rISC pathway. Here we introduce a new, simple route to this end, just through explicit modeling and simulations on routinely available, experimental data from ultrafast transient absorption spectroscopy. We demonstrate on a proof-of-concept, rare-earth chelate molecular system that our approach, featuring spectral profile analysis together with wavelength-dependent global kinetics fitting, enables facile retrieval of the rISC rate from experimental data.

Lighting up long-range charge-transfer states by a localized plasmonic field

Co-reporter:Zhen Xie;Sai Duan;Chuan-Kui Wang

Nanoscale (2009-Present) 2017 vol. 9(Issue 46) pp:18189-18193

Publication Date(Web):2017/11/30

DOI:10.1039/C7NR06322A

The long-range charge-transfer states in a donor–acceptor system exhibit well separated electron–hole pairs, but are often difficult to achieve by optical means owing to a very small overlap between the wave functions of the donor and acceptor. We have found that the introduction of a spatially confined plasmon can enhance the transition probability to the long-range charge-transfer states as it can effectively break the intrinsic symmetry selection rule imposed on the system. Meanwhile, the intensity borrowed from local excitations could also be selectively promoted, allowing the manipulation of the excited quantum states. In addition, our calculations reveal that the donor and acceptor moieties can be unambiguously visualized in real space by tip-enhanced resonance Raman images. These findings can benefit light-harvesting and also be readily extended to diverse optical processes.

Distinguishing Individual DNA Bases in a Network by Non-Resonant Tip-Enhanced Raman Scattering

Co-reporter:Dr. Rui Zhang;Xianbiao Zhang;Huifang Wang;Dr. Yao Zhang;Dr. Song Jiang;Dr. Chunrui Hu;Dr. Yang Zhang; Dr. Yi Luo; Dr. Zhenchao Dong

Angewandte Chemie International Edition 2017 Volume 56(Issue 20) pp:5561-5564

Publication Date(Web):2017/05/08

DOI:10.1002/anie.201702263

AbstractThe importance of identifying DNA bases at the single-molecule level is well recognized for many biological applications. Although such identification can be achieved by electrical measurements using special setups, it is still not possible to identify single bases in real space by optical means owing to the diffraction limit. Herein, we demonstrate the outstanding ability of scanning tunneling microscope (STM)-controlled non-resonant tip-enhanced Raman scattering (TERS) to unambiguously distinguish two individual complementary DNA bases (adenine and thymine) with a spatial resolution down to 0.9 nm. The distinct Raman fingerprints identified for the two molecules allow to differentiate in real space individual DNA bases in coupled base pairs. The demonstrated ability of non-resonant Raman scattering with super-high spatial resolution will significantly extend the applicability of TERS, opening up new routes for single-molecule DNA sequencing.

Distinguishing Individual DNA Bases in a Network by Non-Resonant Tip-Enhanced Raman Scattering

Co-reporter:Dr. Rui Zhang;Xianbiao Zhang;Huifang Wang;Dr. Yao Zhang;Dr. Song Jiang;Dr. Chunrui Hu;Dr. Yang Zhang; Dr. Yi Luo; Dr. Zhenchao Dong

Angewandte Chemie 2017 Volume 129(Issue 20) pp:5653-5656

Publication Date(Web):2017/05/08

DOI:10.1002/ange.201702263

Identifying the structure of 4-chlorophenyl isocyanide adsorbed on Au(111) and Pt(111) surfaces by first-principles simulations of Raman spectra

Co-reporter:Wei Hu;Sai Duan;Yujin Zhang;Hao Ren;Jun Jiang

Physical Chemistry Chemical Physics 2017 vol. 19(Issue 48) pp:32389-32397

Publication Date(Web):2017/12/13

DOI:10.1039/C7CP06329F

Surface Raman spectroscopy has become one of the most powerful analytical tools for interfacial structures. However, theoretical modeling for the Raman spectra of molecular adsorbate on metallic surfaces is a long-standing challenge because accurate descriptions of the electronic structure for both the metallic substrates and adsorbates are required. Here we present a quasi-analytical method for high-precision surface Raman spectra at the first principle level. Using this method, we correlate both geometrical and electronic structures of a single 4-chlorophenyl isocyanide (CPI) molecule adsorbed on a Au(111) or Pt(111) surface with its Raman spectra. The “finger-print” frequency shift of the CN stretching mode reveals the in situ configuration of CPI is vertical adsorption on the top site of the Au(111) surface, but a bent configuration when it adsorbs on the hollow site of the Pt(111) surface. Electronic structure calculations reveal that a π-back donation mechanism often causes a red shift to the Raman response of CN stretching mode. In contrast, σ donation as well as a wall effect introduces a blue shift to the CN stretching mode. A clear relationship for the dependence of Raman spectra on the surface electronic and geometrical information is built up, which largely benefits the understanding of chemical and physical changes during the adsorption. Our results highlight that high-precision theoretical simulations are essential for identifying in situ geometrical and electronic surface structures.

Unraveling the Mechanism for the Sharp-Tip Enhanced Electrocatalytic Carbon Dioxide Reduction: The Kinetics Decide

Co-reporter:Dr. Huijun Jiang; Dr. Zhonghuai Hou; Dr. Yi Luo

Angewandte Chemie International Edition 2017 Volume 56(Issue 49) pp:15617-15621

Publication Date(Web):2017/12/04

DOI:10.1002/anie.201708825

AbstractThe electrocatalytic reduction reaction of carbon dioxide can be significantly enhanced by the use of a sharp-tip electrode. However, the experimentally observed rate enhancement is many orders of magnitudes smaller than what would be expected from an energetic point of view. The kinetics of this tip-enhanced reaction are shown to play a decisive role, and a novel reaction-diffusion kinetic model is proposed. The experimentally observed sharp-tip enhanced reaction and the maximal producing rate of carbon monoxide under different electrode potentials are well-reproduced. Moreover, the optimal performance shows a strong dependence on the interaction between CO2 and the local electric field, on the adsorption rate of CO2, but not on the reaction barrier. Two new strategies to further enhance the reaction rate have also been proposed. The findings highlight the importance of kinetics in modeling electrocatalytic reactions.

Unraveling the Mechanism for the Sharp-Tip Enhanced Electrocatalytic Carbon Dioxide Reduction: The Kinetics Decide

Co-reporter:Dr. Huijun Jiang; Dr. Zhonghuai Hou; Dr. Yi Luo

Angewandte Chemie 2017 Volume 129(Issue 49) pp:15823-15827

Publication Date(Web):2017/12/04

DOI:10.1002/ange.201708825

New Mechanism for Photocatalytic Reduction of CO2 on the Anatase TiO2(101) Surface: The Essential Role of Oxygen Vacancy

Co-reporter:Yongfei Ji and Yi Luo

Journal of the American Chemical Society 2016 Volume 138(Issue 49) pp:15896-15902

Publication Date(Web):November 21, 2016

DOI:10.1021/jacs.6b05695

Photocatalytic reduction of CO2 into organic molecules is a very complicated and important reaction. Two possible pathways, the fast-hydrogenation (FH) path and the fast-deoxygenation (FdO) path, have been proposed on the most popular photocatalyst TiO2. We have carried out first-principles calculations to investigate both pathways on the perfect and defective anatase TiO2(101) surfaces to provide comprehensive understanding of the reaction mechanism. For the FH path, it is found that oxygen vacancy on defective surface can greatly lower the barrier of the deoxygenation processes, which makes it a more active site than the surface Ti. For the FdO path, our calculation suggests that it can not proceed on the perfect surface, nor can it proceed on the defective surface due to their unfavorable energetics. Based on the fact that the FH path can proceed both at the surface Ti site and the oxygen vacancy site, we have proposed a simple mechanism that is compatible with various experiments. It can properly rationalize the selectivity of the reaction and greatly simplify the picture of the reaction. The important role played by oxygen vacancy in the new mechanism is highlighted and a strategy for design of more efficient photocatalysts is proposed accordingly.

Theory for Modeling of High Resolution Resonant and Nonresonant Raman Images

Co-reporter:Sai Duan, Guangjun Tian, and Yi Luo

Journal of Chemical Theory and Computation 2016 Volume 12(Issue 10) pp:4986-4995

Publication Date(Web):September 20, 2016

DOI:10.1021/acs.jctc.6b00592

Tip-enhanced Raman imaging is capable of resolving the inner structure of a single molecule owing to the generation of highly localized nanocavity plasmon. Here we present a general theory and detailed computational methodology to fully describe resonant and nonresonant Raman scattering under the localized plasmonic field. We use an allylcarbinol molecule adsorbed on the gold surface as a model system to illustrate different effects on the Raman images. It is found that the ability of distinguishing an individual vibration mode is highly limited under the resonant condition due to the dominant contribution from the Franck–Condon term and the mode-independent component of the Herzberg–Teller term. The nonresonant Raman images of the single molecule are vibrationally distinguishable and present the vibrational motion of the corresponding vibrational modes in real space. Furthermore, the calculated results confirm that nonlinear optical effects can further improve the resolution of the images. The theoretical and computational methods presented here provide the basic tools to model high resolution Raman images at the single molecular level.

Back Cover: Visualization of Vibrational Modes in Real Space by Tip-Enhanced Non-Resonant Raman Spectroscopy (Angew. Chem. Int. Ed. 3/2016)

Co-reporter:Dr. Sai Duan;Dr. Guangjun Tian;Dr. Yi Luo

Angewandte Chemie International Edition 2016 Volume 55( Issue 3) pp:

Publication Date(Web):

DOI:10.1002/anie.201511087

Visualization of Vibrational Modes in Real Space by Tip-Enhanced Non-Resonant Raman Spectroscopy

Co-reporter:Dr. Sai Duan;Dr. Guangjun Tian;Dr. Yi Luo

Angewandte Chemie International Edition 2016 Volume 55( Issue 3) pp:1041-1045

Publication Date(Web):

DOI:10.1002/anie.201508218

Abstract

We present a general theory to model the spatially resolved non-resonant Raman images of molecules. It is predicted that the vibrational motions of different Raman modes can be fully visualized in real space by tip-enhanced non-resonant Raman scattering. As an example, the non-resonant Raman images of water clusters were simulated by combining the new theory and first-principles calculations. Each individual normal mode gives rise its own distinct Raman image, which resembles the expected vibrational motions of the atoms very well. The characteristics of intermolecular vibrations in supermolecules could also be identified. The effects of the spatial distribution of the plasmon as well as nonlinear scattering processes were also addressed. Our study not only suggests a feasible approach to spatially visualize vibrational modes, but also provides new insights in the field of nonlinear plasmonic spectroscopy.

Visualization of Vibrational Modes in Real Space by Tip-Enhanced Non-Resonant Raman Spectroscopy

Co-reporter:Dr. Sai Duan;Dr. Guangjun Tian;Dr. Yi Luo

Angewandte Chemie 2016 Volume 128( Issue 3) pp:1053-1057

Publication Date(Web):

DOI:10.1002/ange.201508218

Abstract

Rcktitelbild: Visualization of Vibrational Modes in Real Space by Tip-Enhanced Non-Resonant Raman Spectroscopy (Angew. Chem. 3/2016)

Co-reporter:Dr. Sai Duan;Dr. Guangjun Tian;Dr. Yi Luo

Angewandte Chemie 2016 Volume 128( Issue 3) pp:

Publication Date(Web):

DOI:10.1002/ange.201511087

Reorganization of hydrogen bond network makes strong polyelectrolyte brushes pH-responsive

Co-reporter:Bo Wu;Xiaowen Wang;Jun Yang;Zan Hua;Kangzhen Tian;Ran Kou;Jian Zhang;Shuji Ye;Vincent S. J. Craig;Guangzhao Zhang;Guangming Liu

Science Advances 2016 Vol 2(8) pp:e1600579

Publication Date(Web):05 Aug 2016

DOI:10.1126/sciadv.1600579

The pH response of strong polyelectrolyte brushes originates from the pH-mediated reorganization of hydrogen bond network.

Theoretical Modeling of Plasmon-Enhanced Raman Images of a Single Molecule with Subnanometer Resolution

Co-reporter:Sai Duan; Guangjun Tian; Yongfei Ji; Jiushu Shao; Zhenchao Dong

Journal of the American Chemical Society 2015 Volume 137(Issue 30) pp:9515-9518

Publication Date(Web):July 17, 2015

DOI:10.1021/jacs.5b03741

Under local plasmonic excitation, Raman images of single molecules can now surprisingly reach subnanometer resolution. However, its physical origin has not been fully understood. Here we report a quantum-mechanical description of the interaction between a molecule and a highly confined plasmonic field. We show that when the spatial distribution of the plasmonic field is comparable to the size of the molecule, the optical transition matrix of the molecule becomes dependent on the position and distribution of the plasmonic field, resulting in a spatially resolved high-resolution Raman image of the molecule. The resonant Raman image reflects the electronic transition density of the molecule. In combination with first-principles calculations, the simulated Raman image of a porphyrin derivative adsorbed on a silver surface nicely reproduces its experimental counterpart. The present theory provides the basic framework for describing linear and nonlinear responses of molecules under highly confined plasmonic fields.

Visible-Light Photoexcited Electron Dynamics of Scandium Endohedral Metallofullerenes: The Cage Symmetry and Substituent Effects

Co-reporter:Bo Wu; Jiahua Hu; Peng Cui; Li Jiang; Zongwei Chen; Qun Zhang; Chunru Wang

Journal of the American Chemical Society 2015 Volume 137(Issue 27) pp:8769-8774

Publication Date(Web):June 22, 2015

DOI:10.1021/jacs.5b03612

Endohedral metallofullerenes (EMFs) have become an important class of molecular materials for optoelectronic applications. The performance of EMFs is known to be dependent on their symmetries and characters of the substituents, but the underlying electron dynamics remain unclear. Here we report a systematic study on several scandium EMFs and representative derivatives to examine the cage symmetry and substituent effects on their photoexcited electron dynamics using ultrafast transient absorption spectroscopy. Our attention is focused on the visible-light (530 nm as a demonstration) photoexcited electron dynamics, which is of broad interest to visible-light solar energy harvesting but is considered to be quite complicated as the visible-light photons would promote the system to a high-lying energy region where dense manifolds of electronic states locate. Our ultrafast spectroscopy study enables a full mapping of the photoinduced deactivation channels involved and reveals that the long-lived triplet exciton plays a decisive role in controlling the photoexcited electron dynamics under certain conditions. More importantly, it is found that the opening of the triplet channels is highly correlated to the fullerene cage symmetry as well as the electronic character of the substituents.

Bringing light into the dark triplet space of molecular systems

Co-reporter:Jing Ge, Qun Zhang, Jun Jiang, Zhigang Geng, Shenlong Jiang, Kaili Fan, Zhenkun Guo, Jiahua Hu, Zongwei Chen, Yang Chen, Xiaoping Wang and Yi Luo

Physical Chemistry Chemical Physics 2015 vol. 17(Issue 19) pp:13129-13136

Publication Date(Web):20 Apr 2015

DOI:10.1039/C5CP00323G

A molecule or a molecular system always consists of excited states of different spin multiplicities. With conventional optical excitations, only the (bright) states with the same spin multiplicity of the ground state could be directly reached. How to reveal the dynamics of excited (dark) states remains the grand challenge in the topical fields of photochemistry, photophysics, and photobiology. For a singlet–triplet coupled molecular system, the (bright) singlet dynamics can be routinely examined by conventional femtosecond pump–probe spectroscopy. However, owing to the involvement of intrinsically fast decay channels such as intramolecular vibrational redistribution and internal conversion, it is very difficult, if not impossible, to single out the (dark) triplet dynamics. Herein, we develop a novel strategy that uses an ultrafast broadband white-light continuum as a excitation light source to enhance the probability of intersystem crossing, thus facilitating the population flow from the singlet space to the triplet space. With a set of femtosecond time-reversed pump–probe experiments, we report on a proof-of-concept molecular system (i.e., the malachite green molecule) that the pure triplet dynamics can be mapped out in real time through monitoring the modulated emission that occurs solely in the triplet space. Significant differences in excited-state dynamics between the singlet and triplet spaces have been observed. This newly developed approach may provide a useful tool for examining the elusive dark-state dynamics of molecular systems and also for exploring the mechanisms underlying molecular luminescence/photonics and solar light harvesting.

Theoretical spectroscopic studies on chemical and electronic structures of arginylglycine

Co-reporter:Hongbao Li, Leilei Li, Jun Jiang, Zijing Lin and Yi Luo

Physical Chemistry Chemical Physics 2015 vol. 17(Issue 38) pp:24754-24760

Publication Date(Web):04 Aug 2015

DOI:10.1039/C5CP03729H

The energy differences between canonical and zwitterionic isomers of arginylglycine (ArgGly) at the CCSD/aug-cc-pVDZ level are too small (less than 1 kcal mol−1) to determine the dominant form in the gas phase from the energetic point of view. First-principles simulations have been performed for near-edge X-ray absorption fine-structure (NEXAFS) spectra and X-ray photoelectron spectra (XPS) at C, N and O K-edges, as well as for infrared (IR) spectra of neutral ArgGly. Noticeable spectral differences were found which enable the unambiguous identification of different neutral groups. We thus demonstrate X-ray spectroscopy as a powerful technique to study the conformation dependent chemical and electronic properties of neutral ArgGly.

Accurate Determination of Interfacial Protein Secondary Structure by Combining Interfacial-Sensitive Amide I and Amide III Spectral Signals

Co-reporter:Shuji Ye ; Hongchun Li ; Weilai Yang

Journal of the American Chemical Society 2014 Volume 136(Issue 4) pp:1206-1209

Publication Date(Web):January 2, 2014

DOI:10.1021/ja411081t

Accurate determination of protein structures at the interface is essential to understand the nature of interfacial protein interactions, but it can only be done with a few, very limited experimental methods. Here, we demonstrate for the first time that sum frequency generation vibrational spectroscopy can unambiguously differentiate the interfacial protein secondary structures by combining surface-sensitive amide I and amide III spectral signals. This combination offers a powerful tool to directly distinguish random-coil (disordered) and α-helical structures in proteins. From a systematic study on the interactions between several antimicrobial peptides (including LKα14, mastoparan X, cecropin P1, melittin, and pardaxin) and lipid bilayers, it is found that the spectral profiles of the random-coil and α-helical structures are well separated in the amide III spectra, appearing below and above 1260 cm–1, respectively. For the peptides with a straight backbone chain, the strength ratio for the peaks of the random-coil and α-helical structures shows a distinct linear relationship with the fraction of the disordered structure deduced from independent NMR experiments reported in the literature. It is revealed that increasing the fraction of negatively charged lipids can induce a conformational change of pardaxin from random-coil to α-helical structures. This experimental protocol can be employed for determining the interfacial protein secondary structures and dynamics in situ and in real time without extraneous labels.

RRS-PBC: a molecular approach for periodic systems

Co-reporter:Igor Ying Zhang;Jun Jiang;Bin Gao;Xin Xu

Science China Chemistry 2014 Volume 57( Issue 10) pp:1399-1404

Publication Date(Web):2014 October

DOI:10.1007/s11426-014-5183-y

Technically, when dealing with a perfect crystal, methods in k-(reciprocal) space that impose periodic boundary conditions (PBC) in conjunction with plane-wave basis sets are widely used. Chemists, however, tend to think of a solid as a giant molecule, which offers a molecular way to describe a solid by using a finite cluster model (FCM). However, FCM may fail to simulate a perfect crystal due to its inevitable boundary effects. We propose an RRS-PBC method that extracts the k-space information of a perfect crystalline solid out of a reduced real space (RRS) of an FCM. We show that the inevitable boundary effects in an FCM are eliminated naturally to achieve converged high-quality band structures.

Identification of 13- and 14-Coordinated Structures of First Hydrated Shell of [AuCl4]− Acid Aqueous Solution by Combination of MD and XANES

Co-reporter:Qing Ye, Jing Zhou, Ting Zhao, Haifeng Zhao, Wangsheng Chu, Zhengxu Sheng, Xing Chen, Augusto Marcelli, Yi Luo, and Ziyu Wu

The Journal of Physical Chemistry B 2012 Volume 116(Issue 27) pp:7866-7873

Publication Date(Web):June 11, 2012

DOI:10.1021/jp3026623

Molecular dynamics simulations combined with multiple scatting X-ray absorption spectral calculations have been employed to study the local geometry of an [AuCl4]− cluster in acid aqueous solution. It is found that the previously assumed simple octahedral structure with two H atoms located in the axial position of the [AuCl4]− plane fails to correctly reproduce the experimental X-ray absorption spectra. Molecular dynamics simulations have revealed a very complicated first hydrated water shell that mainly consists of 13 or 14 ligand water molecules. In general, the first hydrated water molecules are located in two orthogonal quasi-elliptic surfaces around [AuCl4]− cluster. The water molecules’ configuration in the first hydrated shell is further confirmed by the X-ray absorption spectral analysis, which gives a good agreement with the experiment when the 13-hydrated and 14-hydrated complexes are evenly mixed. It shows the power of the combined molecular dynamics simulations and spectra calculations in determining the local structure of molecular ligands around the metal center.

Tuning Chemical Enhancement of SERS by Controlling the Chemical Reduction of Graphene Oxide Nanosheets

Co-reporter:Xinxin Yu, Hongbing Cai, Wenhua Zhang, Xinjing Li, Nan Pan, Yi Luo, Xiaoping Wang, and J. G. Hou

ACS Nano 2011 Volume 5(Issue 2) pp:952

Publication Date(Web):January 6, 2011

DOI:10.1021/nn102291j

Chemical enhancement is an important mechanism in surface-enhanced Raman spectroscopy. It is found that mildly reduced graphene oxide (MR-GO) nanosheets can significantly increase the chemical enhancement of the main peaks by up to 1 order of magnitude for adsorbed Rhodamine B (RhB) molecules, in comparison with the mechanically exfoliated graphene. The observed enhancement factors can be as large as ∼103 and show clear dependence on the reduction time of graphene oxide, indicating that the chemical enhancement can be steadily controlled by specific chemical groups. With the help of X-ray photoelectron spectra, these chemical species are identified and the origin of the observed large chemical enhancement can thus be revealed. It is shown that the highly electronegative oxygen species, which can introduce a strong local electric field on the adsorbed molecules, are responsible for the large enhancement. In contrast, the local defects generated by the chemical reduction show no positive correlation with the enhancement. Most importantly, the dramatically enhanced Raman spectra of RhB molecules on MR-GO nanosheets reproduce all important spectral fingerprints of the molecule with a negligible frequency shift. Such a unique noninvasive feature, along with the other intrinsic advantages, such as low cost, light weight, easy availability, and flexibility, makes the MR-GO nanosheets very attractive to a variety of practical applications.Keywords (): chemical enhancement; mildly reduced graphene oxide; molecular fingerprint; noninvasive; oxygen-containing groups; surface-enhanced Raman spectroscopy (SERS); π-conjugation

Tuning Magnetism in Transition-Metal-Doped 3C Silicon Carbide Polytype

Co-reporter:Jing Zhou ; Haiming Li ; Linjuan Zhang ; Jie Cheng ; Haifeng Zhao ; Wangsheng Chu ; Jinlong Yang ; Yi Luo ;Ziyu Wu

The Journal of Physical Chemistry C 2011 Volume 115(Issue 1) pp:253-256

Publication Date(Web):December 13, 2010

DOI:10.1021/jp105121y

Structural and magnetic properties of 3d transition-metal-doped silicon carbide in cubic (3C) polytype have been systematically studied from first principles to reconcile conflicting experimental findings. The most energetically favorable structures fall in two distinct sets depending on the character of the 3d transition metal and the Si atomic chemical potential. The structure of substitutional TMSi is the most stable one for early transition metals like Ti, V, Cr, and Mn, while the clustering of TMSi−TMI dimers formed by the neighboring substitutional TMSi and interstitial TMI is energetically favored for late transition metals such as Co, Ni, and Cu. For Fe, the most stable structure is the substitutional configuration under C-rich conditions, while under Si-rich conditions the clustering of the FeSi−FeI dimer is energetically favored. It is found in the doped silicon carbide that the Co dimer is nonmagnetic, while both Ni and Cu atoms interact ferromagnetically and make the whole doped system half metallic. Fe atoms show a ferrimagnetic order with a local magnetic moment of 2.0 and −0.34 μB at substitutional and interstitial sites, respectively. Such intrinsically tunable magnetic properties of 3d transition-metal-doped silicon carbide could find many exciting potential applications in spintronics.

Bringing light into the dark triplet space of molecular systems

Co-reporter:Jing Ge, Qun Zhang, Jun Jiang, Zhigang Geng, Shenlong Jiang, Kaili Fan, Zhenkun Guo, Jiahua Hu, Zongwei Chen, Yang Chen, Xiaoping Wang and Yi Luo

Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 19) pp:NaN13136-13136

Publication Date(Web):2015/04/20

DOI:10.1039/C5CP00323G

Theoretical spectroscopic studies on chemical and electronic structures of arginylglycine

Co-reporter:Hongbao Li, Leilei Li, Jun Jiang, Zijing Lin and Yi Luo

Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 38) pp:NaN24760-24760

Publication Date(Web):2015/08/04

DOI:10.1039/C5CP03729H