| Autor: |
Östmark, Henric, Wallin, Sara, Hore, Nathan, Launila, Olli |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 9/22/2003, Vol. 119 Issue 12, p5918, 5p, 2 Charts, 5 Graphs |
| Abstrakt: |
Raman spectra of solid P[sub 4] have been recorded from 12 K up to room temperature using Fourier transform-Raman spectroscopy. The three Raman-active modes corresponding to T[sub d] symmetry have been resolved, and line shifts depending on temperature and matrix environment have been measured. Two phase transitions have been observed at T≈80 K (irreversible) and T≈195 K (reversible) corresponding to the γ→β and β↔α transitions, respectively. In the β phase, the ν[sub 2] mode is split into two lines, ν[sub split]≈7.7 cm[sup -1]. The splitting of the ν[sub 2] mode is an indication of a breaking of T[sub d] symmetry for the β phase. A matrix shift of ≈3 cm-1 for P[sub 4] in a N[sub 2] matrix (1:5) was measured. Comparing experimental transitions of pure P[sub 4] with literature values on matrix isolated P[sub 4] in N[sub 2] (1:1000) we can conclude that there is a matrix shift in nitrogen of between 6 and 9 cm-1 depending on vibrational mode. The line positions found for pure P[sub 4] in the γ phase at 12 K are ν[sub 1]=599.8 cm[sup -1], ν[sub 2]=361.6 cm[sup -1], and ν[sub 3]=459.0 cm[sup -1]. The corresponding values in the α phase at 220 K are ν[sub 1]=598.8 cm[sup -1], ν[sub 2]=360.6 cm[sup -1], and ν[sub 3]=458.0 cm[sup -1]. The present work also adds valuable insight into the behavior of other potential molecules with similar T[sub d] structure such as N[sub 4](T[sub d]). © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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