The lanthanide or lanthanoid series of chemical elements comprises at least the 14 metallic chemical elements with atomic numbers 57–70, from lanthanum through ytterbium. In the periodic table, they fill the 4f orbitals. Lutetium is also sometimes considered a lanthanide, despite being a d-block element and a transition metal.
Praseodymium is a chemical element; it has symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered one of the rare-earth metals. It is a soft, silvery, malleable and ductile metal, valued for its magnetic, electrical, chemical, and optical properties. It is too reactive to be found in native form, and pure praseodymium metal slowly develops a green oxide coating when exposed to air.
Europium(III) chloride is an inorganic compound with the formula EuCl3. The anhydrous compound is a yellow solid. Being hygroscopic it rapidly absorbs water to form a white crystalline hexahydrate, EuCl3·6H2O, which is colourless. The compound is used in research.
Nickel(II) bis(acetylacetonate) is a coordination complex with the formula [Ni(acac)2]3, where acac is the anion C5H7O2− derived from deprotonation of acetylacetone. It is a dark green paramagnetic solid that is soluble in organic solvents such as toluene. It reacts with water to give the blue-green diaquo complex Ni(acac)2(H2O)2.
Tris(acetylacetonato) iron(III), often abbreviated Fe(acac)3, is a ferric coordination complex featuring acetylacetonate (acac) ligands, making it one of a family of metal acetylacetonates. It is a red air-stable solid that dissolves in nonpolar organic solvents.
Metal acetylacetonates are coordination complexes derived from the acetylacetonate anion (CH
3COCHCOCH−
3) and metal ions, usually transition metals. The bidentate ligand acetylacetonate is often abbreviated acac. Typically both oxygen atoms bind to the metal to form a six-membered chelate ring. The simplest complexes have the formula M(acac)3 and M(acac)2. Mixed-ligand complexes, e.g. VO(acac)2, are also numerous. Variations of acetylacetonate have also been developed with myriad substituents in place of methyl (RCOCHCOR′−). Many such complexes are soluble in organic solvents, in contrast to the related metal halides. Because of these properties, acac complexes are sometimes used as catalyst precursors and reagents. Applications include their use as NMR "shift reagents" and as catalysts for organic synthesis, and precursors to industrial hydroformylation catalysts. C
5H
7O−
2 in some cases also binds to metals through the central carbon atom; this bonding mode is more common for the third-row transition metals such as platinum(II) and iridium(III).
Dysprosium acetylacetonate is a chemical compound of dysprosium with formula Dy(C5H7O2)3(H2O)n.
Gadolinium acetylacetonate is a coordination compound with the formula Gd(C5H7O2)3. This anhydrous acetylacetonate complex is widely discussed but unlikely to exist per se. The 8-coordinated dihydrate Gd(C5H7O2)3(H2O)2 is a more plausible formula based on the behavior of other lathanide complexes. It has also been characterized twice by X-ray crystallography.
Rhodium acetylacetonate is the coordination complex with the formula Rh(C5H7O2)3, which is sometimes known as Rh(acac)3. The molecule has D3-symmetry. It is a yellow-orange solid that is soluble in organic solvents.
Tris(acetylacetonato)cobalt(III) is the coordination complex with the formula Co(C5H7O2)3. Often abbreviated Co(acac)3, it is a green, diamagnetic solid that is soluble in organic solvents, but not in water. Owing to its solubility in organic solvents, tris(acetylacetonato)cobalt(III) is used to produce homogeneous catalysts by reduction.
Neodymium(III) acetylacetonate is a coordination compound with the chemical formula Nd(O2C5H7)3. Although many sources discuss this anhydrous acetylacetonate complex, it is the dihydrate Nd(O2C5H7)3(H2O)2 that has been characterized by X-ray crystallography. It commonly occurs as a white powder. Upon heating under vacuum, other dihydrated lanthanide trisacetylacetonates convert to oxo-clusters M4O(C5H7O2)10. This result suggests that Nd(O2C5H7)3 may not exist.
Europium compounds are compounds formed by the lanthanide metal europium (Eu). In these compounds, europium generally exhibits the +3 oxidation state, such as EuCl3, Eu(NO3)3 and Eu(CH3COO)3. Compounds with europium in the +2 oxidation state are also known. The +2 ion of europium is the most stable divalent ion of lanthanide metals in aqueous solution. Many europium compounds fluoresce under ultraviolet light due to the excitation of electrons to higher energy levels. Lipophilic europium complexes often feature acetylacetonate-like ligands, e.g., Eufod.
Holmium acetylacetonate is a coordination compound with the formula Ho(C5H7O2)3. This anhydrous acetylacetonate complex is often discussed but unlikely to exist per se. The 8-coordinated dihydrate Ho(C5H7O2)3(H2O)2 is a more plausible formula based on the behavior of other lanthanide acetylacetonates. The dihydrate has been characterized by X-ray crystallography.
Yttrium acetylacetonate is a coordination compound with the chemical formula Y(C5H7O2)3(H2O)x, or Y(acac)3(H2O)x for short. The value of x can vary from 1 to 3.
Praseodymium acetylacetonate is a coordination complex with the formula Pr(C3H7O2)3. This purported anhydrous acetylacetonate complex is widely discussed but only the dihydrate Pr(C3H7O2)3(H2O)2 has been characterized by X-ray crystallography.
Erbium acetylacetonate is a coordination compound with the formula Er(C5H7O2)3. This anhydrous acetylacetonate complex is often discussed but unlikely to exist per se. The 8-coordinated dihydrate Er(C5H7O2)3(H2O)2 is a more plausible formula based on the behavior of other lanthanide acetylacetonates. The dihydrate has been characterized by X-ray crystallography.
Thulium acetylacetonate is a coordination compound with the formula Tm(C5H7O2)3. This anhydrous acetylacetonate complex is often discussed but unlikely to exist per se. The 8-coordinated dihydrate Tm(C5H7O2)3(H2O)2 is a more plausible formula based on the behavior of other lanthanide acetylacetonates. The dihydrate has been characterized by X-ray crystallography. Upon attempted dehydration by heating under vacuum, other hydrated lanthanide tris(acetylacetonate) complexes decompose to give oxo-clusters.
Lanthanum acetylacetonate refers to the coordination complex with the formula La(C5H7O2)3. This anhydrous acetylacetonate complex has not been characterized well, but the dihydrate La(C5H7O2)3(H2O)2 has been characterized by X-ray crystallography.
Samarium acetylacetonate is a coordination compound with the formula Sm(C5H7O2)3. This anhydrous acetylacetonate complex is widely discussed but unlikely to exist per se. The 8-coordinated dihydrate Sm(C5H7O2)3(H2O)2 is a more plausible formula based on the behavior of other lanthanide acetylacetonates. The dihydrate has been characterized by X-ray crystallography. Upon attempted dehydration by heating under vacuum, other hydrated lanthanide tris(acetylacetonate) complexes decompose to give oxo-clusters.
Ytterbium(III) acetylacetonate is a coordination compound with the chemical formula Yb(C5H7O2)3(H2O)2. Its structure is different from the acetylacetone complexes of neodymium, europium and holmium. The adjacent Yb-Yb The distance is 8.3 Å. Yb(acac)3(bpy) can be obtained by reacting its trihydrate with 2,2'-bipyridine in ethanol.
