摘要:

AbstractThe results obtained using a variety of new solid supports for the preparation of surface‐enhanced Raman‐active substrates via direct chemical reduction of silver salts and by vacuum vapor deposition of metallic silver are presented. These supports include two small pore size cellulose filter papers and frosted glass slides. These supports yield silver substrates with a much more uniform silver particle size and distribution than observed on previously used supports such as Whatman No. 1 and No. 5 filter papers. Results obtained using a solid silver membrane filter are also presented. These substrates provide metal particle morphology which is uniform on a submicrometer scale. This degree of uniformity is necessary for enhancing the reproducibility of SERS using a Raman microprobe since the area probed by this microprobe is 5–10 μm2. By using filter papers and glass slides, coupled with the vapor deposition and chemical reduction techniques, the resulting substrates are also fast, simple, and inexpensive, making them ideal candidates for routine an

ISSN:0377-0486    

DOI:10.1002/jrs.1250221002

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractA simple optical low‐temperature icing cell was fabricated to obtain thein situRaman spectra of ice layers forming on metallic substrates. The icing cell is optically coupled to a micro Raman multi‐channel spectrometer. The Raman spectra of the initial ice layers show characteristics of a disordered phase resembling low‐density amorphous ice. The crystalline phase develops gradually as the thickness of the ice layer increases. The disorder in the initial ice layer may be caused primarily by the rapid thermal cooling, and appears to be independent of the type of metal subs

ISSN:0377-0486    

DOI:10.1002/jrs.1250221003

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractRaman spectra were obtained for crystalline Li(I), Na(I), K(I), Ba(II) and Cd(II) salts of uridine 5′‐monophosphoric acid. Assignments were made based chiefly on a comparison of the vibrational data observed for these compounds with those of uracil and D‐ribose‐5‐phosphate and on normal coordinate calculations. Some Raman spectral features, mainly in the 1420‐1350 and 700‐600 cm−1ranges, seem to reflect the conformational structure of the

ISSN:0377-0486    

DOI:10.1002/jrs.1250221004

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractPolarized Raman spectra of single crystals of KIO4and RbIO4were obtained. The observed fundamental modes satisfy the selection rules valid for the scheelite structure. The pressure dependence of the Raman spectra of KIO4, which was investigated up to 12 Gpa, reveals a structural phase transition in the crystal near 6.5 GPa, where new peaks are observed. Above 9.8 GPa only the peaks belonging to the high‐pressure phase exis

ISSN:0377-0486    

DOI:10.1002/jrs.1250221005

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractRaman spectra of thin films of the TiO2crystal modifications anatase and rutile are reported. The oxides are easily synthesized by electrochemical oxidation of titanium electrodes under controlled conditions. Evidence for the formation of a third crystal modification, possibly brookite, is presented.

ISSN:0377-0486    

DOI:10.1002/jrs.1250221006

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractThe infrared and polarized Raman spectra of the amino acidL‐glutamic acid in the crystalline state have been recorded and measured. The data obtained have been used to propose a general assignment of the vibrational fundamentals on the intensity changes observed in the polarized Raman spectra and correlations with frequencies assigned in other amino acids and related molecule

ISSN:0377-0486    

DOI:10.1002/jrs.1250221007

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractHigh‐resolution polarized and depolarized resonance Raman spectra of isotopically pure molecular bromine (79Br2) with Δν = 1–5 were recorded using the argon laser lines at 501.7, 496.5, 488.0, 476.5, 457.9, 363.8, 351.1 and 333.6 nm and the Kr laser line 413.1 nm. Using a high‐sensitive CCD camera, the experimentally obtained spectra have better signal‐to‐noise ratios than some of the spectra already published. All observed spectra were also calculated using second‐order perturbation theory. The high sensitivity of resonance Raman band shapes to changes in the position of excited potential curves gives the possibility of determining the potential functions of the excited states1II1uand3II0+uin the energy range between 20 000 and 30 000 cm−1very accurately. These potentials allow a satisfactory description of all observed spectra, including those of the overtones, in contrast

ISSN:0377-0486    

DOI:10.1002/jrs.1250221008

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractThe polarized Raman and IR spectra of Mg(NH4)2(HPO4)2·4H2O and its partially deuterated polycrystalline sample were recorded and analysed. The presence of bands characteristic of HPO2−4and DPO2−4ions are interpreted in terms of the proton polarizabilities of the HPO2−4and jDPO2−4ions. The ammonium ion is free to rotate in the crystal and crystallographically distinct NH4+ions exist. Hydrogen bonding of different groups is also d

ISSN:0377-0486    

DOI:10.1002/jrs.1250221009

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

摘要:

AbstractSurface enhanced Raman scattering (SERS) has been used to investigate the structure, surface reaction and enhancement mechanism of adsorbed molecules on metal surfaces. However, a major limitation has been having to choose the molecules with functional groups capable of adsorbing onto metal surfaces. We report here SERS of Ni(II) tetrasulphonate phthalocyanine (Ni(II)PCS) as a result of introducing cationic surfactants like CTAB or CTAC. Ni(II)PCS does not adsorb onto a silver surface by itself and consequently does not show any SERS effect. The cationic surfactants employed here have functional groups to adsorb onto a silver surface and simultaneously interact with anionic sulphonate groups of Ni(II)PCS. Surfactant‐aided SERS would expand the range of SERS application to molecules which are not able to adsorb onto metal surfaces by themselve

ISSN:0377-0486    

DOI:10.1002/jrs.1250221010

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY

ISSN:0377-0486    

DOI:10.1002/jrs.1250221001

出版商:John Wiley&Sons, Ltd.    

年代:1991

数据来源: WILEY