Structures, thermal behaviors, and luminescent properties of anhydrous lanthanum iodate polymorphs

Inorganic Chemistry
Mohamed B TaoutiIsabelle Gautier-Luneau

Abstract

The structural and thermal studies of six anhydrous lanthanum iodate polymorphs are presented. The variation of the [IO3(-)]:[La(3+)] molar ratio in the starting solution and the evaporation rate of the solution leads to either the centric La(IO3)3(HIO3) or the acentric La(IO3)3(HIO3)1.33 phases. The crystal structure of La(IO3)3(HIO3)1.33 was determined. The thermal treatments of these two phases up to 490 °C lead to β-La(IO3)3, observed at room temperature. To better understand the similar thermal behaviors of La(IO3)3(HIO3)1.33 and La(IO3)3(HIO3) compounds and their structural evolution, thermogravimetry-differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC) analyses and in situ temperature-dependent powder X-ray diffraction (XRD) experiments were carried out. These experiments allowed us to highlight the successive formation of δ-La(IO3)3 and γ-La(IO3)3. δ-La(IO3)3 is observed from the beginning of thermal decomposition of La(IO3)3(HIO3)1.33 (at 340 °C) or La(IO3)3(HIO3) (at 300 °C) up to 440 °C. A phase transition from δ-La(IO3)3 to γ-La(IO3)3 then occurs at 440 °C. Finally, the phase transition from γ-La(IO3)3 to β-La(IO3)3 occurs at 140 °C. A cycle of heating and cooling shows the reversible phas...Continue Reading

References

Jan 1, 1995·Acta Crystallographica. Section A, Foundations of Crystallography·R H Blessing
Feb 6, 2009·Journal of the American Chemical Society·Hong-Young ChangKang Min Ok
Nov 29, 2004·Optics Express·Peter Dekker, Judith Dawes
Jun 24, 2009·Journal of the American Chemical Society·Chuan-Fu SunJiang-Gao Mao
Mar 25, 2011·Journal of the American Chemical Society·Chuan-Fu SunJiang-Gao Mao

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.