![]() Where more than one isotope exists, the value given is the abundance weighted average.Ītoms of the same element with different numbers of neutrons. This is approximately the sum of the number of protons and neutrons in the nucleus. The mass of an atom relative to that of carbon-12. The transition of a substance directly from the solid to the gas phase without passing through a liquid phase.ĭensity is the mass of a substance that would fill 1 cm 3 at room temperature. The temperature at which the liquid–gas phase change occurs. The temperature at which the solid–liquid phase change occurs. The arrangements of electrons above the last (closed shell) noble gas. These blocks are named for the characteristic spectra they produce: sharp (s), principal (p), diffuse (d), and fundamental (f). The atomic number of each element increases by one, reading from left to right.Įlements are organised into blocks by the orbital type in which the outer electrons are found. Members of a group typically have similar properties and electron configurations in their outer shell.Ī horizontal row in the periodic table. ISBN 1-4398-5511-0.A vertical column in the periodic table. CRC Handbook of Chemistry and Physics (92nd ed.). Digital Imaging Systems for Plain Radiography. "Digital Radiography Detectors: A Technical Overview" (PDF). Infrared Spectroscopy for Food Quality Analysis and Control. "Luminescence and scintillation properties of CsI: A potential cryogenic scintillator". "Polymorphism of cesium and thallium halides". "Atomic structure and dynamic behaviour of truly one-dimensional ionic chains inside carbon nanotubes". ^ a b Senga, Ryosuke Komsa, Hannu-Pekka Liu, Zheng Hirose-Takai, Kaori Krasheninnikov, Arkady V."Quantum efficiency of cesium iodide photocathodes at soft x-ray and extreme ultraviolet wavelengths". "Equation of state and high-pressure phase transition of CsI". In addition to image intensifier input phosphors, caesium iodide is often also used in medicine as the scintillating material in flat panel x-ray detectors. They should also be coated (typically with germanium) and stored in a desiccator, to minimize interaction with atmospheric water vapors. However, optical-quality CsI crystals are very soft and hard to cleave or polish. It has a wider transmission range than the more common potassium bromide beamsplitters, working range into the far infrared. The drawbacks of CsI are a high temperature gradient and a slight hygroscopicity.Ĭaesium iodide is used as a beamsplitter in Fourier transform infrared (FTIR) spectrometers. It shows two main emission components: one in the near ultraviolet region at the wavelength of 310 nm and one at 460 nm. Pure CsI is a fast and dense scintillating material with relatively low light yield that increases significantly with cooling. Properties Solubility of Csl in water Т (☌)Īn important application of caesium iodide crystals, which are scintillators, is electromagnetic calorimetry in experimental particle physics. As a result, Cs atoms are attracted to the walls and vibrate more strongly than I atoms, which are pushed toward the nanotube axis. This difference was explained by the charge difference between Cs atoms (positive), inner nanotube walls (negative) and I atoms (negative). In such chains I atoms appear brighter than Cs atoms in electron micrographs despite having a smaller mass. Ĭaesium iodide atomic chains can be grown inside double-wall carbon nanotubes. ![]() ![]() īulk caesium iodide crystals have the cubic CsCl crystal structure, but the structure type of nanometer-thin CsI films depends on the substrate material – it is CsCl for mica and NaCl for LiF, NaBr and NaCl substrates. Synthesis and structure Monatomic caesium halide wires grown inside double-wall carbon nanotubes. Caesium iodide photocathodes are highly efficient at extreme ultraviolet wavelengths. It is often used as the input phosphor of an X-ray image intensifier tube found in fluoroscopy equipment. Caesium iodide or cesium iodide ( chemical formula CsI) is the ionic compound of caesium and iodine. ![]()
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