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Lanthanide metals react exothermically with hydrogen to form LnH 2, dihydrides. [1] With the exception of Eu and Yb, which resemble the Ba and Ca hydrides (non-conducting, transparent salt-like compounds),they form black pyrophoric, conducting compounds [6] where the metal sub-lattice is face centred cubic and the H atoms occupy tetrahedral sites. [1]
Despite this, the use of lanthanide coordination complexes as homogeneous catalysts is largely restricted to the laboratory and there are currently few examples them being used on an industrial scale. [36] Lanthanides exist in many forms other than coordination complexes and many of these are industrially useful.
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), [1] are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals.
The lanthanides become harder as the series is traversed: as expected, lanthanum is a soft metal. Lanthanum has a relatively high resistivity of 615 nΩm at room temperature; in comparison, the value for the good conductor aluminium is only 26.50 nΩm.
EuFOD, an example of a europium complex. It has been known since the early 1930s that the salts of certain lanthanides are fluorescent. [4] The reaction of lanthanide salts with nucleic acids was discussed in a number of publications during the 1930s and the 1940s where lanthanum-containing reagents were employed for the fixation of nucleic acid structures. [3]
Other considerations about the host lattice include choice of cation and anions. Importantly, cations should have similar radii to the intended dopant ions: For example, when using lanthanide dopant ions, certain alkaline-earth (Ca 2+), rare-earth (Y +), and transition-metal ions (Zr 4+) all fulfill this requirement, as well as Na +. Similarly ...
Lanthanum chloride is also used in biochemical research to block the activity of divalent cation channels, mainly calcium channels.Doped with cerium, it is used as a scintillator material.