Molecular Science最新文献_第2页

Femtosecond Structural Dynamics of Complex Molecular Systems Studied by Time-Domain Raman Spectroscopy Using Few-Cycle Pulses 用时域拉曼光谱研究复杂分子体系的飞秒结构动力学

Molecular Science Pub Date : 2021-01-01 DOI: 10.3175/molsci.15.a0117

H. Kuramochi

{"title":"Femtosecond Structural Dynamics of Complex Molecular Systems Studied by Time-Domain Raman Spectroscopy Using Few-Cycle Pulses","authors":"H. Kuramochi","doi":"10.3175/molsci.15.a0117","DOIUrl":"https://doi.org/10.3175/molsci.15.a0117","url":null,"abstract":"One of the frontiers in modern chemical science is to observe nuclear rearrangements during a chemical reaction in real time and unveil structure-function interplay underlying the sophisticated functions of complex molecular systems. In this quest, various time-resolved techniques have been developed in the last decades. Nevertheless, it has not yet been trivial to track structural changes of the molecules proceeding on the time scale of the nuclear motion, i.e., femto-to-picosecond time scale. Recently, we developed femtosecond time-resolved time-domain Raman spectroscopy using < 7-fs pulses, which allows us to track structural changes of the molecules on the femtosecond time scale with exquisite sensitivity. With this technique, we realized real-time observation of the ultrafast structural dynamics in the primary photochemical/photophysical processes in condensed-phase complex molecular systems. In this article, we overview the principle and a brief history of time-domain Raman spectroscopy and then describe the apparatus and recent applica-tions to the femtosecond dynamics of molecules as complex as photoreceptor proteins and molecular assemblies.","PeriodicalId":19105,"journal":{"name":"Molecular Science","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78658469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Conventional and Unconventional View of Chiro-Optical Effects (Optical Activity) 传统与非传统的手旋光效应(旋光性)观点

Molecular Science Pub Date : 2021-01-01 DOI: 10.3175/molsci.15.a0119

Hiromi Okamoto

引用次数: 0

Theoretical Study of Lanthanide Luminescence Materials 镧系发光材料的理论研究

Molecular Science Pub Date : 2021-01-01 DOI: 10.3175/molsci.15.a0118

Miho Hatanaka

引用次数: 0

Development of Time-Resolved Heterodyne-Detected Vibrational Sum Frequency Generation Spectroscopy and Its Application to Interfacial Dynamics 时间分辨外差检测振动和频率产生谱的发展及其在界面动力学中的应用

Molecular Science Pub Date : 2021-01-01 DOI: 10.3175/molsci.15.a0116

Ken‐ichi Inoue

引用次数: 0

Development of Single-Molecule Science 单分子科学的发展

Molecular Science Pub Date : 2021-01-01 DOI: 10.3175/molsci.15.a0120

M. Taniguchi

{"title":"Development of Single-Molecule Science","authors":"M. Taniguchi","doi":"10.3175/molsci.15.a0120","DOIUrl":"https://doi.org/10.3175/molsci.15.a0120","url":null,"abstract":"We reviewed the single-molecule science based on single-molecule measurements using tunneling current and ionic current as probes. Single-molecule measurements using tunneling currents can determine the number of molecules connected to a nanogap electrode. In addition, single-molecule measurements enable measuring the molecular vibration, local temperature, thermoelectric power, and electrode-molecule binding energy of a single molecule connected between electrodes. In addition, as a physical quantity, the phase information of the frontier molecular orbital of single molecules is measured. On the other hand, using an ionic current, single-molecule measurements enable highly accurate identification of a bacterium or virus that passes through a nanopore having a through-hole with a diameter of several μ m or less. Nanopores are also a stage for elucidating the flow dynamics of a single substance transported in a liquid confined in a nanospace. Single-molecule science, which is growing as a fundamental discipline, is advancing to applied research targeting biomolecules. Furthermore, the fusion of single-molecule measurements and artificial intelligence will enable data analysis methods that are different from conventional ones. It is also becoming possible to investigate the properties of a single molecule rather than the statistical average molecular behavior.","PeriodicalId":19105,"journal":{"name":"Molecular Science","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82561156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Structural Biological Study Based on Spectroscopic Analysis of Cone Pigment 基于视锥色素光谱分析的结构生物学研究

Molecular Science Pub Date : 2021-01-01 DOI: 10.3175/molsci.15.a0115

Kota Katayama

{"title":"Structural Biological Study Based on Spectroscopic Analysis of Cone Pigment","authors":"Kota Katayama","doi":"10.3175/molsci.15.a0115","DOIUrl":"https://doi.org/10.3175/molsci.15.a0115","url":null,"abstract":"Vitamin A is adequately distributed within the body to maintain the biological function of retinoids in the periph-eral tissues and the production of the visual chromophore, 11- cis -retinal, in the eye. One of the mysteries in our vision is that humans recognize color by use of a single chromophore molecule (11- cis -retinal), meaning that the chromophore is identical even between blue-absorbing and red-absorbing sensors. Humans have two different types of retinal contain-ing light-sensitive proteins expressed in the retina, rhodopsin (Rh) achieving the twilight vision and three cone pigments, which mediate color vision. Each different chromophore-protein interaction allows preferential absorption of a selected range of wavelengths. While the structural basis for photoreaction and signal transduction of Rh has been well understood by the determination of its atomic-level structure, structural studies of cone pigments lag far behind those of Rh, mainly because of difficulty in sample preparation and lack of suitable methods in structural analysis. We thus attempted to express monkey cone pigments in HEK293 cell lines for structural analysis using light-induced difference Fourier-transform infrared (FTIR) spectroscopy. The first structural information successfully elicited from the highly accurate spectra for each cone pigment showed that the retinal chromophore is structurally similar between Rh and cone pigments, but the hydrogen-bonding network around the retinal chromophore is entirely different between them. In addition, some spectral differences are observed between cone pigments, including protein-bound water molecules. These differences could be interpreted to play a role in spectral tuning.","PeriodicalId":19105,"journal":{"name":"Molecular Science","volume":"88 22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84072175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Systematic Approach to Electron Correlation via Spin-symmetry Breaking and Restoration 通过自旋对称破缺和恢复的电子相关的系统方法

Molecular Science Pub Date : 2020-01-01 DOI: 10.3175/molsci.14.a0109

T. Tsuchimochi

引用次数: 0

Advances in Molecular Spectroscopy in Condensed Phase and Quantum Chemistry 凝聚态与量子化学分子光谱学研究进展

Molecular Science Pub Date : 2020-01-01 DOI: 10.3175/molsci.14.a0114

Y. Ozaki

{"title":"Advances in Molecular Spectroscopy in Condensed Phase and Quantum Chemistry","authors":"Y. Ozaki","doi":"10.3175/molsci.14.a0114","DOIUrl":"https://doi.org/10.3175/molsci.14.a0114","url":null,"abstract":"1. はじめに分子分光学は 19世紀の終わりに誕生し,20世紀に大きく発展した。20世紀中の進歩の非常に大きな部分は,最後の 30年ばかりの間に起こったと考えてよい。とくに重要なのは,レーザーが広く普及した 70年代の進歩である。筆者が関係したラマン分光学を見てみると,共鳴ラマン,表面増強ラマン散乱(SERS),顕微ラマン,非線形ラマン,時間分解ラマン,ラマン光学活性など今日,非常に注目されている様々なラマン分光法のほとんどが 70年代に誕生した。ラマンに限らず紫外可視,けい光分光の顕微分光法や時間分解分光法も同じである。レーザーだけのおかげではないが,レーザーの発展が果たした役割は果てしなく大きい。80年代には FT-IRが広く普及し,顕微赤外,時間分解赤外などが大きく進展した。90年代に入ると,まず近赤外分光法が成長し ,さらにその後半になるとテラヘルツ分光法(terahertz time-domain spectroscopy; THz-TDS) が登場した。凝集相に関して言えば,20世紀の最後になって紫外域(145 nm)から遠赤外/テラヘルツ領域(3.3 cm-1; 0.1 THz)までシームレスに繋がったのである。 90年代に入るまでは,レーザーや分光器,検出器などハードの進歩が大方分光学の進歩を引っ張ってきたわけであるが,90年代に入るとソフトの進歩も分光学を支えるようになった。とくに量子化学の発展が目覚ましい。振動分光学,電子分光学など分子分光学のどの分野においても量子化学は中心的な役割を果たしている。ケモメトリックスも分光学にかなり寄与した。ケモメトリックスは,最初は主に分析化学的応用に用いられたが,最近では物理化学的な研究にも盛んに用いられている。21世紀に入り,約 10 年前に筆者らは ATR法を遠紫外域に導入することにより, 凝集相の分子分光学を 145 nm(8.5 eV)まで拡張した。 21世紀に入りようやく凝集相の分子分光学が,遠紫外から遠赤外/テラヘルツまで拡がったのである。量子化学の分子分光学への応用においてとくに重要な出来事は,1964年のK. Kohnらによる密度汎関数法(Density","PeriodicalId":19105,"journal":{"name":"Molecular Science","volume":"50 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78267533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Heterodyne-Detected Chiral Vibrational Sum Frequency Generation and Its Applications 外差检测手性振动和频率的产生及其应用

Molecular Science Pub Date : 2020-01-01 DOI: 10.3175/molsci.14.a0111

Masanari Okuno

引用次数: 0

“Hidden Frustration” in Molecule-based K4 and Diamond Lattices Revealed by the Line Graph Transformation 线形变换揭示分子基K4和金刚石晶格中的“隐藏挫折”

Molecular Science Pub Date : 2020-01-01 DOI: 10.3175/molsci.14.a0113

R. Suizu, K. Awaga

引用次数: 0