caesium

Definitions

  • WordNet 3.6
    • n caesium a soft silver-white ductile metallic element (liquid at normal temperatures); the most electropositive and alkaline metal
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Webster's Revised Unabridged Dictionary
    • n caesium (Chem) A rare alkaline metal found in mineral water; -- so called from the two characteristic blue lines in its spectrum. It was the first element discovered by spectrum analysis, and is the most strongly basic and electro-positive substance known. Symbol Cs. Atomic number 55. Atomic weight 132.6.
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Century Dictionary and Cyclopedia
    • n caesium Chemical symbol, Cs; atomic weight, 132.8. A rare metal discovered by Bunsen and Kirchhoff by spectrum analysis in the saline waters of Dürkheim in Germany, and subsequently in other mineral waters. It has never been isolated, and is only known in combination. It is a strong base belonging, with potassium, sodium, lithium, and rubidium, to the group of alkali metals. Cæsium, in connection with rubidium, is found most abundantly in the lepidolite of Hebron, Maine. The oxalate and nitrate or cæsium are used in medicine.
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Chambers's Twentieth Century Dictionary
    • n Caesium sēz′i-um a silver-white, soft, and extensile alkaline metal, almost always found along with rubidium, discovered by Bunsen and Kirchhoff in 1860 by spectrum analysis
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Etymology

Webster's Revised Unabridged Dictionary
NL., from L. caesius, bluish gray
Chambers's Twentieth Century Dictionary
L. cæsius, bluish gray.

Usage

In literature:

This residue consists of sodium, potassium and lithium chlorides, with small quantities of caesium and rubidium chlorides.
"Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4" by Various
Thus Bunsen in 1860 discovered two new alkaline metals, Caesium and Rubidium.
"Logic, Inductive and Deductive" by William Minto
What is the vapour density of Caesium?
"The Scientific Basis of National Progress" by George Gore
Caesium chlorid c. p., 2 grams, was fed in aqueous solution to a rabbit weighing 1,077.2 grams.
"Barium, A Cause of the Loco-Weed Disease" by Albert Cornelius Crawford
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In science:

During the observation, the data regularly receive a time stamp, usually based on a caesium time standard or hydrogen maser at the observatory plus a signal from the Global Positioning System of satellites (GPS; ).
Binary and Millisecond Pulsars at the New Millennium
The cryogenic sapphire oscillator (CSO) is compared to a commercial (Datum Inc.) active hydrogen maser whose frequency is also regularly compared to caesium and rubidium atomic fountain clocks in the laboratory .
Tests of relativity using a microwave resonator
In addition new theoretical calculations brought the atomic parity violation in Caesium from a 1.5σ deviation exactly to the Standard Model prediction.
Electroweak Precision Data and the Higgs Mass - Workshop Summary
In fact, the sign conventions have been changed compared to in order to share the definitions of the particle data group 2 . A sample use is prepared with subroutine ZF APV, with N = 78 and Z = 55 for Caesium.
ZFITTER: a semi-analytical program for fermion pair production in e+e- annihilation, from version 6.21 to version 6.42
PV asymmetry in Møller scattering , and the APV measurements in caesium.
Pump-probe measurement of atomic parity violation in caesium with a precision of 2.6%
One application of the model is to simulate the pressure-induced isostructural phase transition in materials such as caesium.
Two-band second moment model and an interatomic potential for caesium
Caesium adopts the bcc structure (Cs I) at ambient pressure, transforming under slight additional pressure to fcc (Cs II) and under further increase transforming isostructurally to fcc (Cs III) .
Two-band second moment model and an interatomic potential for caesium
In the present case, we are interested in the gross features of the model, so we adopt simple forms fitted to the cohesive energies and volume of the high and low pressure polytypes of caesium.
Two-band second moment model and an interatomic potential for caesium
The predicted equilibrium volume of the ambient pressure phase agrees well with the experimental equilibrium volume of phase I of caesium.
Two-band second moment model and an interatomic potential for caesium
TABLE I: Parameters for the two band model, obtained by fitting to phases II and III of caesium.
Two-band second moment model and an interatomic potential for caesium
FIG. 2: Top: Variation of ηi with compression, showing s → d transfer in model caesium (T = 1).
Two-band second moment model and an interatomic potential for caesium
In reality caesium also has a bcc-fcc phase transition at 2.3 GPa, however first principles calculations show that these two structures are almost degenerate in energy at 0K.
Two-band second moment model and an interatomic potential for caesium
For a detailed study of point defects in caesium, it would be appropriate to reparametrise the potential with point defects included in the fitting, but the good results obtained here without such fitting suggest that the present model contains the right physics.
Two-band second moment model and an interatomic potential for caesium
The parameters E0 , As , Ad , Cs , Cd , ds and dd are taken from the fit to caesium, with the lengths being scaled according to the Fermi vector (Z−1/3 ) and the energies by (Z 1/2 ).
Two-band second moment model and an interatomic potential for caesium
Extension of the formalism to transition metals is straightforward, and the caesium parametrisation gives a surprisingly good description across the group.
Two-band second moment model and an interatomic potential for caesium
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