Topic
Raspite
About: Raspite is a research topic. Over the lifetime, 19 publications have been published within this topic receiving 393 citations.
Papers
TL;DR: The Raman and IR spectra of monoclinic naturally occurring raspite, α-PbWO4 (space group P21/a) were measured; it is irreversibly transformed to the tetragonal stolzite, β-pbWOWO4, by heating to 450°C, and this process was followed by Raman spectroscopy as mentioned in this paper.
Abstract: The Raman and IR spectra of monoclinic naturally occurring raspite, α-PbWO4 (space group P21/a) were measured; it is irreversibly transformed to the tetragonal stolzite, β-PbWO4, by heating to 450°C, and this process was followed by Raman spectroscopy. Assignments of fundamental modes are proposed. New data are also presented on single crystals of stolzite (space group I41/a), and it is shown that raspite and stolzite can easily be distinguished by their Raman spectra. We also present Raman and IR spectroscopic data on natural and synthetic studtite, UO4·4H2O, and its synthetic dehydration product metastudtite, UO4·2H2O, the only two naturally occurring peroxide-containing minerals, and on partially deuterated synthetic forms of these materials. Assignments of fundamental modes are proposed and both TGA and DSC data are presented for studtite. Copyright © 2004 John Wiley & Sons, Ltd.
95 citations
TL;DR: In this article, a facile composite-salt-mediated synthesis method was proposed to obtain raspite PbWO4 nanobelts without using any surface-capping agent.
Abstract: Raspite PbWO4, which is rare in nature, poses a great challenge to laboratory preparation and only limited optical and spectroscopic investigations have been conducted on raspite PbWO4 crystals from nature. In this article, we report that raspite PbWO4 nanobelts can be obtained by a facile composite-salt-mediated synthesis method without using any surface-capping agent. The nanobelts are well crystallized with lengths up to hundreds of microns. The synthesis method is simple and cost effective. Our investigation demonstrates that the raspite PbWO4 nanobelts possess excellent blue–green luminescent property at low temperature and highly sensitive photocurrent response to light switches at room temperature. The growth mechanism of the raspite PbWO4 nanobelts, the structure characteristic and the luminescent mechanism are discussed in detail.
26 citations
TL;DR: The first synthesis of monoclinic raspite PbWO(4) in the laboratory, which usually exists as a natural crystal, is demonstrated and the photoluminescence properties of the obtained PbwO( 4) crystals with different morphologies and crystal structures have been characterized and discussed.
Abstract: A facile, dextran-directed solution route for the morphology- and structure-controlled synthesis of PbWO4 crystals, such as monoclinic raspite PbWO4 nanobelts and tetragonal stolzite PbWO4 crystals with penniform and wheat-ear-like morphologies, has been demonstrated Three differently charged dextrans were employed for the PbWO4 crystallization and they turned out to be very effective in the morphological and structural modulation of PbWO4 crystals, as evidenced by the scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD) and Raman spectroscopy characterizations In particular, novel monoclinic raspite PbWO4 nanobelts were produced under the direction of anionic dextran with a suitable concentration, probably due to the specific interactions between SO42− groups from anionic dextran molecules and Pb2+ ions from PbWO4 crystals To the best of our knowledge, this is the first synthesis of monoclinic raspite PbWO4 in the laboratory, which usually exists as a natural crystal In addition, the photoluminescence properties of the obtained PbWO4 crystals with different morphologies and crystal structures have been characterized and discussed, which provides useful information for the fundamental investigation and potential application of PbWO4 crystals
25 citations
TL;DR: In this paper, the reflection and luminescence spectra of scheelite and raspite-structured PbWO 4 crystals were studied at 6 K with use of synchrotron radiation as a light source.
22 citations
TL;DR: In this paper, lead tungstate PbWO4 single crystals were grown from sodium metasilicate gel and water solutions of lead acetate and sodium tungstane as the reagents.
Abstract: Lead tungstate PbWO4 single crystals were grown from sodium metasilicate gel and water solutions of lead acetate and sodium tungstate as the reagents. Crystals grown were several micrometer in size and by X-ray diffraction measurements it was determined that they are only of the scheelite structure. No evidence of lead tungstate low temperature modification – raspite – was found. The emission properties of crystals were measured over the temperature interval 80 to 300 K and it was found that they are similar to those in PbWO4 crystals grown by the Czochralski method.
20 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2017 | 1 |
| 2014 | 1 |
| 2012 | 1 |
| 2011 | 2 |
| 2010 | 2 |
| 2008 | 2 |