Refinement of the Crystal Structure of Thenardite, Na2SO4(V).

Nord, Anders G.; Sværen, Stein Egil; Møller, Jørgen; Schroll, Gustav; Leander, Kurt; Swahn, Carl‐Gunnar

doi:10.3891/acta.chem.scand.27-0814

Cited by 76 publications

(56 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sodium atoms are each surrounded by 6 oxygen atoms each at 2.334Å, 2.426Å, and 2.534Å forming distorted NaO 6 octahedra with a two fold axis parallel toaxis. The O-Na-O angles, 56.15 ∘ -134.93 ∘ , are greatly distorted from octahedral symmetry [12,13]. All the sulphate ions are separated from each other by distances >3Å for two oxygen atoms belonging to different sulphate groups.…”

Section: Powder X-ray Diffraction Analysismentioning

confidence: 99%

“…Each SO 4 tetrahedron shares two of its edges with two different 2.534Å representing the distances to oxygen's forming the shared tetrahedral edge. The remaining corners of the NaO 6 octahedron are shared with another four SO 4 tetrahedron there giving a 3D framework [12,13]. Mirabilite (phase III) also has an orthorhombic crystal structure with space group mcm .…”

Section: Powder X-ray Diffraction Analysismentioning

confidence: 99%

See 1 more Smart Citation

Preparation, Characterization, and Luminescence Properties of Orthorhombic Sodium Sulphate

Vidya

Lakshminarasappa

2013

Physics Research International

View full text Add to dashboard Cite

A highly efficient thermoluminescence Na 2 SO 4 phosphor with thenardite polymorphic structure was prepared by simple slow evaporation technique followed by subsequent calcination at 200 ∘ C, 400 ∘ C, and 600 ∘ C for 4 h and the resultant crystals were characterized by various analytical techniques. All the samples exhibited thermodynamically stable thenardite phase and the grain growth was increased for the calcined samples. SEM analysis indicated the fine distribution of twinned orthogonal prism and pyramidal structure without any agglomeration. The electron spin resonance spectroscopy showed the existence of SO 4 − radicals as trap centre. The thermoluminescence behavior suggested the charge carrier recombination dynamics in the thenardite sample followed second-order kinetics. The trapping parameters such as activation energy ( ), order of kinetics ( ), and frequency factor ( ) have been determined using Chen's peak shape method. Further fading of the TL intensity of Na 2 SO 4 showed that thenardite is quite suitable for radiation dosimetry even up to 15 days. The photoluminescence band of Na 2 SO 4 reduced in its intensity after -irradiation, suggesting that defects are unstable and decay rapidly.

show abstract

Section: Powder X-ray Diffraction Analysismentioning

confidence: 99%

Section: Powder X-ray Diffraction Analysismentioning

confidence: 99%

Preparation, Characterization, and Luminescence Properties of Orthorhombic Sodium Sulphate

Vidya

Lakshminarasappa

2013

Physics Research International

View full text Add to dashboard Cite

show abstract

“…fl-K2SO 4 (McGinnety, 1972), 1.476 A in Na2SO4(V ) (Nord, 1973a), and 1-473 A in LizSO4 (Nord, 1973b). The S-O distances have also been corrected for the thermal vibrations of the atoms by means of the ridingmotion model (Busing & Levy, 1964).…”

mentioning

confidence: 99%

Low-temperature rubidium sulphate

Nord¹

1974

Acta Crystallogr Sect B

View full text Add to dashboard Cite

Abstract.fl-Rb2SO4, orthorhombic, Pnam, a = 7.8128 (5), b=10-4255 (7), c=5.9694 (5) A (25°C); Z=4, calculated density 3.647 g cm -3. Crystals were grown from a melt of Rb2SO4. The structure has been refined by least-squares methods to give an R value of 0"055 for 634 diffractometer-measured reflexions. The present work has confirmed the general features of the atomic arrangement reported by Ogg [Phil. Mag. (1928). 5, 354-367]. The rubidium ions are surrounded by nine or eleven oxygen atoms. The SO~-tetrahedra are regular with an average S-O distance of 1.474 A.

show abstract

“…Similarly, a qualitative observation has been made for the system prepared at 600°C. Na 2 SO 4 exists in phase V at room temperature; orthorhombic symmetry (space group F ddd ) [24], while PbTiO 3 exhibits a tetragonal structure (space group P 4mm ) [25] PbTiO 3 transforms from the tetragonal to the cubic structure at 490°C which has been confirmed using DSC. The X-ray diffractogram confirms composite formation.…”

Section: Resultsmentioning

confidence: 71%