Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Raman scattering study of phase transitions in NH4SCN (1985)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 82 (1985), S. 5624-5632 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The Raman spectra (30–3300 cm−1) of a single crystal and of polycrystalline forms of NH4SCN are presented in the temperature range 135 to −175 °C. The polarization behavior of the Raman bands reveals the antipolar arrangements of SCN− ions in the room temperature phase. Above 86.5 °C the spectra do not show polarization behavior due to the formation of polycrystalline domains. Other changes observed in the entire spectrum at this phase transition are attributed to reorientation of SCN− ions between two equivalent configurations. At the next phase transition around 112 °C the lattice modes of SCN− ions are affected. The characteristics are those of a second-order displacive phase transition. A new phase transition observed at −70 °C is characterized by the strengthening of the hydrogen-bond networks in the lattice.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.448598
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Raman scattering and vibrational dynamics of MnCl2·2H2O (1978)
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 7 (1978), S. 202-204 
    Details
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The laser excited Raman spectrum of MnCl2·2H2O has been reported in the 4000-150 cm-1 region and discussed in conjunction with the known IR spectra. The bands have been assigned to internal and librational modes of water and other lattice modes. It has been found that the correlation splitting parameter Δν/νmean is distinctly larger for the librational modes than for the internal modes of water. The increase in intensity of the ν1 over the ν3 band of water in passing from the free to crystal water state and the low intensity of the librational bands have been explained.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jrs.1250070408
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Incommensurate phase in tetramethylammonium tetrachlorozincate: Evidence from internal modes (1986)
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 17 (1986), S. 345-349 
    Details
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Temperature-dependent vibrational Raman studies of tetramethylammonium tetrachlorozincate [(TMA)2ZnCl4] are reported together with the assignments of the observed bands in all the six polarization geometries at room temperature in phase I, which is orthorhombic with a space group D2h16 (Z=4). Existence of the well known incommensurate phase with wave vector κ = 2/5+δ in the temperature range 296.6-280.9 K is supported by the abnormal intensity behaviour of modes of species A1 (under the point group symmetry Td for TMA and ZnCl4 ions) in X(ZZ)Y and X(YZ)Y polarization geometries. The observed intensity behaviour could be explained on the assumption that the orientations of TMA and ZnCl4 ions are governed by the incommensurate modulation in the Z-direction.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jrs.1250170410
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...