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Wyniki wyszukiwania dla: RESONANCE RAMAN-SPECTRA
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Calculation of Vibrational Resonance Raman Spectra of Molecules Using Quantum Chemistry Methods
PublikacjaThe understanding and interpretation of experimental resonance Raman (RR) spectra can strongly benefit from theoretical simulations. These can be achieved by combining quantum chemistry (QC) methods to calculate the electronic and vibrational molecular properties, together with appropriate models and approximations to compute the Raman intensities. This chapter presents the main and most commonly employed approaches to calculate...
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Resonance Raman Study on Carbon Nanotubes Formation
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Algorithms of chemicals detection using raman spectra
PublikacjaRaman spectrometers are devices which enable fast and non-contact identification of examined chemicals. These devices utilize the Raman phenomenon to identify unknown and often illicit chemicals (e.g. drugs, explosives)without the necessity of their preparation. Now, Raman devices can be portable and therefore can be more widely used to improve security at public places. Unfortunately, Raman spectra measurements is a challenge...
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Algorithms of Chemicals Detection Using Raman Spectra
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Analysis and characterization of coordination compounds by resonance Raman spectroscopy
PublikacjaResonance Raman spectroscopy has become a powerful tool to study excited-state geometries, excited-state charge distributions and photoinduced reaction dynamics in coordination compounds. Due to their rich photophysical properties coordination compounds are utilized for a variety of applications ranging from DNA sensing to photocatalysis. This review features recent applications of various resonance Raman scattering techniques...
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Mixture Model Based Efficient Method for Magnetic Resonance Spectra Quantification
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Resonance-Raman spectro-electrochemistry of intermediates in molecular artificial photosynthesis of bimetallic complexes
PublikacjaThe sequential order of photoinduced charge transfer processes and accompanying structure changes were analyzed by UV-vis and resonance-Raman spectroscopy of intermediates of a Ru(II) based photocatalytic hydrogen evolving system obtained by electrochemical reduction.
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Raman Spectra Measurements for Chemical Identifications - Aspect of Uncertainty Sources and Reduction of Their Effects
PublikacjaRaman spectrometers enable fast and non-contact identification of examined chemicals. These devices measure Raman spectra and compare with the spectra database to identify unknown and often illicit chemicals (e.g. drugs, explosives) usually without any sample preparation. Raman spectra measurements are a challenge due to noise and interferences present outside the laboratories (field applications). The design of a portable Raman...
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Theoretical Assessment of Excited State Gradients and Resonance Raman Intensities for the Azobenzene Molecule
PublikacjaThe ground state geometries and vibrational frequencies as well as the excitation energies and excited state gradients of the S 1(nπ*) and S 2(ππ * ) states of trans - and cis -azobenzene are investigated by several DFT methods, namely B3LYP, PBE, M06-2X, CAM-B3LYP, and ω B97X. Excited state properties and in particular gradients are also assessed using the wave function based methods EOM-CCSD and RASPT2/RASSCF. Comparison with...
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A Novel Ru(II) Polypyridine Black Dye Investigated by Resonance Raman Spectroscopy and TDDFT Calculations
PublikacjaThe optical properties of a new(bipyridine)2Ru(4H-imidazole) complex presenting a remarkablebroad absorption in the visible range are investigated. Thestrong overlap of the absorption with the solar radiationspectrum renders the studied complex promising as a blackabsorber and hence as a starting structure for applications inthe field of dye-sensitized solar cells. The correlations betweenstructural and electronic features for...
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Influence of silver-core gold-shell nanoparticle parameters on the variation of surface-enhanced Raman spectra
PublikacjaThe detection of molecules by surface-enhanced Raman spectroscopy (SERS) is dependent on the nanomaterial used to induce the enhancement effect. This depends on a variety of parameters of the substrate such as the metal used for their creation, their shape, size and size distribution, concentration, as well as the parameters of the solution, such as packing of the nanoparticles, the complexity of the sample, the solvent, etc. It...
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An Assessment of RASSCF and TDDFT Energies and Gradients on an Organic Donor−Acceptor Dye Assisted by Resonance Raman Spectroscopy
PublikacjaThe excitation energies and gradients in the ground and the first excited state of a novel donor−(π- bridge)−acceptor 4-methoxy-1,3-thiazole-based chromophore were investigated by means of MS-RASPT2/RASSCF and TDDFT in solution. Within both methods, the excitation energies strongly depend on the employed equilibrium structures, whose differences can be rationalized in terms of bond length alternation indexes. It is shown that functionals with...
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Raman spectra of CPMH and CPMD
Dane BadawczeThese data contains Raman spectra of CPMH and CPMD. Raman scattering was measured with a RenishawmicroRaman spectrometer (785 nm). Sample abbreviations (CPMH, CPMD) are in agreement with the markings used in the linked publication.
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Sum-over-state expressions including second-order Herzberg–Teller effects for the calculation of absorption and resonance Raman intensities
PublikacjaThe sum-over-state expressions are derived to calculate the second-order Herzberg–Teller (HT) effects in absorption and resonance Raman spectroscopies. These effects depend on the second derivatives of the transition dipole moment with respect to the vibrational coordinates. The method is applied to the molecule of 1,3-butadiene using density functional theory calculations. It is found that the second-order HT effects are significant...
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The role of Herzberg-Teller effects on the resonance Raman spectrum of trans-porphycene investigated by time dependent density functional theory.
PublikacjaThe S1 excited state properties as well as the associated absorption and resonance Raman (RR) spectra of trans-porphycene are investigated by means of time dependent density functional theory calculations. The relative magnitude of the Franck-Condon (FC) contribution and of the Herzberg-Teller (HT) effects is evaluated for both the absorption and RR intensities. The accuracy of the calculated spectra is assessed by employing different...
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Ab initio study of phenyl benzoate: structure, conformational analysis, dipole moment, IR and Raman vibrational spectra
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Raman spectra of MXenes catalysts
Dane BadawczeData contain results from Raman spectroscopy of the Ti3C2Tx MXenes produced via acidic etching aluminum from MAX Phase (Ti3C2-Al-Ti3C2-Al-Ti3C2) using different etching agents, HF/HCl and HF/H2SO4 with different weight ratios (1:3, 1:4, and 1:5). The samples were labeled as MXene HF/HCl X:Y and MXene HF/H2SO4 X:Y, where X:Y means the acids weight ratios. ...
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On Raman optical activity sign-switching between the ground and excited states leading to an unusual resonance ROA induced chirality
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Comparison of simplified sum-over-state expressions to calculate resonance Raman intensities including Franck-Condon and Herzberg-Teller effects
PublikacjaSum-over-state (SOS) expressions to simulate absorption spectroscopy and resonance Raman (RR) scattering including Franck-Condon (FC) and Herzberg-Teller (HT) effects are described. Starting from the general SOS method, several simplified SOS formulae are derived. In particular, within the so-called independent mode displaced harmonic oscillator model, it is shown that including the vibronic structure in the absorption and RR spectra...
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Raman spectra for pyrolized natural compounds
Dane BadawczeThe presented data showcases the results of Raman spectroscopy analysis conducted on pyrolyzed natural compounds both with and without the inclusion of graphene. The study delved into four specific compounds: methylcellulose with lysine (ML), methylcellulose with lysine-graphene composite (MLG), algae (A), and algae-graphene composite (AG). Raman spectra...
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Raman spectra and electrochemical data of carbon nanowall with tailored defects
Dane BadawczeThis dataset comprises of Raman spectra aquired with different excitation laser sources and the electrochemical data of defect-induced carbon nanowall electrodes (CNW).
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Paracetamol in Friction Ridge Skin Raman Spectra - Paracetamol Reference and from drugs 2023
Dane BadawczeRaman scatter spectra for paracetamol from different drugs and paracetamol reference.
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Acetaminophen in Friction Ridge Skin Raman Spectra - acetaminophen (paracetamol) Reference and from drugs 2023
Dane BadawczeRaman spectra for acetaminophen (paracetamol) from different drugs and paracetamol reference.
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Raman spectra of PCMCA-X (potassium citrate derived porous carbon materials obtained at various temperatures of carbonization)
Dane BadawczeThese data contain Raman spectra of PCMCA-700 (potassium citrate derived porous carbon materials obtained at 700°C ), PCMCA-800 (potassium citrate derived porous carbon materials obtained at 800°C ), PCMCA-900 (potassium citrate derived porous carbon materials obtained at 900°C ). The D peak at 1340 cm−1 and the G peak at 1592 cm−1 can be seen in all...
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Raman spectra of WS2/userGOx (composites of tungsten disulfide and ultrafast self-expanded and reduced graphene oxide) and ex-WS2 (exfoliated tungsten disulfide)
Dane BadawczeThese data contain Raman spectra of WS2/userGOx (composites of tungsten disulfide and ultrafast self-expanded and reduced graphene oxide) and ex-WS2 (exfoliated tungsten disulfide). The data were collected for samples obtained from three ex-WS2:GO dispersions - with 1:1, 1:2, and 2:1 weight ratios.
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A spectroscopic study of the cis/trans-isomers of penta-2,4-dienoic acid attached to gold nanoclusters
PublikacjaIn this theoretical work, we present a spectroscopic analysis of the cis/trans-isomers of a molecular switch, penta-2,4-dienoic acid, attached to gold clusters of different size (1, 2 and 20 gold atoms). We have simulated 4 different spectroscopic techniques: Infrared spectroscopy, normal Raman scattering, absorption spectra and resonance Raman scattering. We discuss how the position and the conformation of the molecule determine...
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Feasibility study of a Raman spectroscopic route to drug detection
PublikacjaWe present an surface-enhanced Raman spectroscopy (SERS) approach for detection of drugs of abuse in whole human blood. We utilize a near infrared laser with 830 nm excitation wavelength in order to reduce the influence of fluorescence on the spectra of blood. However, regular plasmon resonance peak of plasmonic nanoparticles, such as silver or gold fall in a much lower wavelength regime about 400 nm. Therefore, we have shifted...
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Redox State Sensitive Spectroscopy of the Model Compound [(H-dcbpy)(2)Ru-II(NCS)(2)](2-) (dcbpy=2,2 '-Bipyridine-4,4 '-dicarboxylato)
PublikacjaThe charge transfer reaction mechanism in a ruthenium polypyridine model complex with isothiocyanato ligands, i.e., [(H-dcbpy)(2)Ru(NCS)(2)](2-) 2Bu(4)N(+) (Ru2H) (dcbpy = 2,2'-bipyridine-4,4'-dicarboxylato), has been investigated by combining UV-vis absorption, resonance Raman spectroscopy, and electrochemical methods. Understanding the photophysics of light-harvesting complexes of this class is an indispensable prerequisite to...
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Properties of Thermally Dewetted Thin Au Films on ITO-Coated Glass for Biosensing Applications
PublikacjaNoble metal nanostructures are object of great interest due to their unique optical and electronic properties exploited in nanotechnology, medicine, biochemistry, and surface-enhanced spectroscopies. In this work, the Au nanoparticle (NP) structures for application in biosensing obtained by dewetting are investigated in dependence on their preparation conditions. Structures are produced from thin Au films (5–30 nm) sputtered onto...
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Raman spectroscopic investigation of blood and related materials
PublikacjaThis paper reports preliminary studies on use of Raman spectroscopy for investigation of blood. High quality blood spectra were recorded in-vitro with excitation wavelengths of 830 nm. Because of complex composition of the blood as well as by light attenuation and scattering in the tissues, spectra set up from wide, low-intensive Raman bands and intensive optical background. To get information about origin of bands in Raman spectra...
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Raman studies of 3D printed CB-PLA samples after microwave treatment
Dane BadawczeThis dataset contains Raman spectroscopy analyses of microwave-activated carbon-black doped polylactic acid 3D printed electrodes.
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Algorytmy przetwarzania widm Ramana w procesie detekcji substancji chemicznych
PublikacjaRozprawa przedstawia szczegółowo algorytmy, jakie są stosowane podczas przetwarzania widm Ramana, rejestrowanych przenośnym spektrometrem o skończonej rozdzielczości. Pracę podzielono na osiem rozdziałów. W pierwszym określono cel i tezy pracy. Rozdział drugi opisuje podstawowe pojęcia dotyczące zjawiska Ramana oraz zasady budowy urządzeń do pomiarów widm Ramana. W rozdziale trzecim scharakteryzowano błędy występujące podczas pomiarów...
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Synthesis and Properties of the Ba2PrWO6 Double Perovskite
PublikacjaWe report details on the synthesis and properties of barium praseodymium tungstate, Ba2PrWO6, a double perovskite that has not been synthesized before. Room-temperature (RT) powder X-ray diffraction identified the most probable space group (SG) as monoclinic I2/m, but it was only slightly distorted from the cubic structure. X-ray photoelectron spectroscopy confirmed that the initial (postsynthesis) material contained praseodymium...
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Noise sources in Raman spectroscopy of biological objects
PublikacjaWe present an overview of noise sources deteriorating the quality of the recorded biological Raman spectra and the ability to determine the specimen composition. The acquired Raman spectra exhibit intense additive noise components or drifts because of low intensity of the scattered light. Therefore we have to apply expensive or bulky measurement setups to limit their inherent noise or to apply additional signal processing to reduce...
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Noise in biological Raman spectroscopy
PublikacjaRaman spectroscopy is a widely used method to investigate chemical molecules by analyzing their vibrational transitions. It utilizes inelastic scattering of the laser light irradiating the investigated object. The scattered light requires appropriate filtering to reduce dominant laser light and expose much weaker components having shifted wavelengths of a characteristic spectral pattern. These components are measured by dispersing...
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Metody usuwania zakłóceń podczas pomiarów polowych widm Ramana
PublikacjaW pracy zostały scharakteryzowane źródła zakłóceń występujące podczas pomiarów widm Ramana w warunkach polowych oraz sposoby redukcji ich wpływu na jakość rejestrowanych widm. Zaprezentowano wpływ czasu integracji na jakość rejestrowanych widm w przypadkach, gdy szumy własne spektrometru mają składową typu 1/f, dominującą w zakresie małych częstotliwości. Przedstawiono także wyniki uzyskane podczas pomiarów z detekcją synchroniczną,...
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Metody usuwania zakłóceń podczas pomiarów polowych widm Ramana
PublikacjaW pracy zostały scharakteryzowane źródła zakłóceń występujące podczas pomiarów widm Ramana w warunkach polowych. Zaprezentowano wpływ czasu integracji na jakość rejestrowanych widm w przypadkach, gdy szumy własne spektrometru mają składową typu 1/f, dominującą w zakresie małych częstotliwości. Przedstawiono także wyniki uzyskane podczas pomiarów z detekcją synchroniczną, stosowaną w przenośnych spektrometrach Ramana, w pomiarach...
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Ni-based compounds in multiwalled graphitic shell for electrocatalytic oxygen evolution reactions
Dane BadawczeThis study investigates Ni-based compounds (Ni, NiO, Ni3C) coated with a graphitic shell as electrocatalysts for the oxygen evolution reaction (OER). Electron paramagnetic resonance (EPR) and X-ray diffraction (XRD) are employed to identify the presence and contribution of Nickel ions (Ni0, Ni2+, Ni3+) and determine the phase composition. Electrochemical...
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Raman spectroscopy analysis of synthesized sol-gel silica coatings
Dane BadawczeThese data contains Raman spectra of silica coatings synthesized using sol-gel method A and B, which were described with publication associated with this dataset. Raman scattering was measured with a Renishaw microRaman spectrometer (830 nm).
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The control software of the portable raman spectrometer
PublikacjaThe paper contains a description of the control software of a portable Raman spectrometer which was built in the Department of Optoelectronics and Electronic Systems Faculty of Electronics, Telecommunications and Informatics Gdansk University of Technology. The software has modular structure, which includes the laser control module and the spectrum acquisition module (laser power selection, working mode and data acquisition time)...
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SEM and Raman studies B:CNWs and BDD electrode used for electrochemical paraquat determination
Dane BadawczeThe dataset contains the scanning electron micrographs (SEM) and Raman spectra of B:CNWs and BDD samples deposited by MW-PECVD. SEM was used to characterise the morphology of BDD and B:CNW. In contrast, RAMAN was used to reveal the main differences in the crystalline structure of BDD and B:CNWs.
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Comparability of Raman Spectroscopic Configurations: A Large Scale Cross-Laboratory Study
PublikacjaThe variable configuration of Raman spectroscopic platforms is one of the major obstacles in establishing Raman spectroscopy as a valuable physicochemical method within real-world scenarios such as clinical diagnostics. For such real world applications like diagnostic classification, the models should ideally be usable to predict data from different setups. Whether it is done by training a rugged model with data from many setups...
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Sensing of anesthetic drugs in blood with Raman spectroscopy
PublikacjaA proof-of-concept study of a Raman spectroscopy-based approach for measuring the content of anesthesia drugs in blood is presented. Spectra of spiked blood from several patients exhibit prominent changes in regions associated with the drug.
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Detection of propofol concentrations in blood by Raman spectroscopy
PublikacjaIn this paper we present a proof-of-concept of a Raman spectroscopy-based approach for measuring the content of propofol, a common anesthesia drug, in whole human blood, and plasma, which is intended for use during clinical procedures. This method utilizes the Raman spectroscopy as a chemically–sensitive method for qualitative detection of the presence of a drug and a quantitative determination of its concentration. A number of...
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Raman investigation of the patina layers on Hungarian copper ingots from a fifteenth century shipwreck
PublikacjaWe report results of the patina study of underwater archeological finding ofmedieval copper objects performed by means of the Raman and complementary spectroscopic techniques. The objects were found submerged in the sea as cargo part of the ship which sunk in the Gulf of Gdańsk in 1408. The excavated collection consists of 230 oval ingots of the size and mass up to about 60 cm and 18 kg (total of 2 tons), respectively. In the Raman...
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Raman data of based on BDD, Mn-BDD, Mn-BDD(AN) electrodes
Dane BadawczeRaman spectra of samples : ion implanted BDD (Mn-BDD) films; prepared by high dose (1015-1017 ions/cm2) Mn ion implantation and post-annealing treatment.
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Studies on novel BiyXz-TiO2/SrTiO3 composites: Surface properties and visible light-driven photoactivity
PublikacjaA series of novel BiyXz-TiO2/SrTiO3 composites were prepared by multistep synthesis route. The asprepared photocatalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), Fourier transform infrared (FT-IR), Raman spectra and BET analysis. The photocatalytic activity test was performed in aqueous solution of phenol under...
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Fabrication of high-density nitrogen-vacancy (NV) center-enriched diamond particles through methyl trityl amine (C20H19N) seeding
PublikacjaDiamond particles (DPs) show promise for advanced applications in bioimaging and quantum sensing due to the presence of defect centers. This work reports a unique growth process for diamond particles composed of nitrogen-vacancy centers (NV-DPs) using a methyl trityl amine (C20H19N) diamondoid seed, which acts as a nitrogen source for NV creation. Growth was performed via microwave plasma-assisted chemical vapor deposition in a...
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Anatomy of noise in quantitative biological Raman spectroscopy
PublikacjaRaman spectroscopy is a fundamental form of molecular spectroscopy that is widely used to investigate structures and properties of molecules using their vibrational transitions. It relies on inelastic scattering of monochromatic laser light irradiating the specimen. After appropriate filtering the scattered light is dispersed onto a detector to determine the shift from the excitation wavelength, which appears in the form of...
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Raman spectroscopy analysis of poly(lactic acid)-carbon black composite treated by femtosecond laser
Dane BadawczeThe dataset contains the Raman spectroscopy measurements of commercially available carbon black-filled poly(lactic acid) 3D printed electrodes after femtosecond laser ablation. These results were utilized in the manuscript published in Electrochimica Acta: 10.1016/j.electacta.2022.140288