Search results
Results from the WOW.Com Content Network
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]
Organolanthanide chemistry is the field of chemistry that studies organolanthanides, compounds with a lanthanide-carbon bond. Organolanthanide compounds are different from their organotransition metal analogues in the following ways: They are far more air- and water-sensitive and are often pyrophoric.
Lanthanide-carbon σ bonds are well known; however as the 4f electrons have a low probability of existing at the outer region of the atom there is little effective orbital overlap, resulting in bonds with significant ionic character.
A steel bottle containing MgCp 2 (magnesium bis-cyclopentadienyl), which, like several other organometallic compounds, is pyrophoric in air.. Organometallic compounds are distinguished by the prefix "organo-" (e.g., organopalladium compounds), and include all compounds which contain a bond between a metal atom and a carbon atom of an organyl group. [2]
Diarylmercurials are often used to synthesize lanthanide organometallic complexes. Hg(C 6 F 5) 2 is a better RT reagent to use with lanthanides than HgPh 2 because it does not require a step to activate the metal. [8] However, phenyl-substituted lanthanide complexes are more thermally stable than the pentafluorophenyl complexes.
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. [28] [29] Lanthanum is the least volatile of the lanthanides. [30]
Neodymium compounds are compounds formed by the lanthanide metal neodymium (Nd). In these compounds, neodymium generally exhibits the +3 oxidation state, such as NdCl 3, Nd 2 (SO 4) 3 and Nd(CH 3 COO) 3. Compounds with neodymium in the +2 oxidation state are also known, such as NdCl 2 and NdI 2. Some neodymium compounds have colors that vary ...
LaC 2 reacts with water to form acetylene, C 2 H 2 and a mixture of complex hydrocarbons. [3] LaC 2 is a metallic conductor, in contrast to CaC 2 which is an insulator. [3] The crystal structure of LaC 2 shows that it contains C 2 units with a C-C bond length of 130.3 pm, which is longer than the C-C bond length in calcium carbide, 119.2 pm, which is close to that of ethyne. [3]