| Autor: |
Ambrosetti, Roberto, Angelone, Rocco, Murgich, Juan |
| Zdroj: |
Zeitschrift für Naturforschung A; February 1986, Vol. 41 Issue: 1-2 p299-304, 6p |
| Abstrakt: |
The FT-NQR spectra of 14N in both pyridine and pyridine-D 5 show four sets of resonance lines at - 196 °C, which disappear reversibly at - 191.5 °C and - 187 °C, respectively. This is interpreted as a phase transition, possibly of the order-disorder type. The NQR results can thus be reconciled with X-ray measurements at - 180 °C which suggested a single site for pyridine. The similarity of the NQR spectra of different samples of both compounds, frozen and cooled with widely different procedures, suggests that the high multiplicity of the NQR spectra is not the result of coexistence of different crystal phases. It is shown that previously available data from IR, Raman and NQR spectroscopies can all be put in a non-contradictory scheme. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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