Lutetium electron configuration

Group 3 of the Periodic Table consists of the elements scandium, yttrium and either lanthanum or lutetium, depending upon the preferred arrangement of the Table. Group 3 elements have the outer electronic configuration ns2 p, and invariably their solution chemistry is that of the + 3 state. In this text, treatment of both La and Lu is carried out in Chapter 8, which deals with the f-block elements. Lanthanum and lutetium represent the first and last members of the lanthanide series. 

The lanthanide elements are the 15 elements from lanthanum to lutetium. Both La and Lu have been included to allow for the different versions of the Periodic Table, some of which position La in Group 3 as the first member of the third transition series and others that place Lu in that position. If Lu is considered to be the first element in the third transition series, all members of that series possess a filled shell 4f14 configuration. The outer electronic configurations of the lanthanide elements are given in Table 8.1. 

Rare Earth elements (REEs) elements that occur in the periodic table from lanthanum (La) to lutetium (Lu)—have similar chemical and physical properties due to their electronic configurations. 

The mechanism for polymerization of propylene with heterogeneous catalysts is very similar to that of ethylene. Studies with a homogeneous catalyst of a lanthanide element provided early mechanistic evidence. The complex used in these studies was 6.15. In 6.15 lutetium is in a 3+ oxidation state and has the electronic configuration of 4fu. In other words Lu3+ has a full/shell and 6.15 is a diamagnetic complex. 

Lanthanide elements (referred to as Ln) have atomic numbers that range from 57 to 71. They are lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). With the inclusion of scandium (Sc) and yttrium (Y), which are in the same subgroup, this total of 17 elements are referred to as the rare earth elements (RE). They are similar in some aspects but very different in many others. Based on the electronic configuration of the rare earth elements, in this chapter we will discuss the lanthanide contraction phenomenon and the consequential effects on the chemical and physical properties of these elements. The coordination chemistry of lanthanide complexes containing small inorganic ligands is also briefly introduced here [1-5]. 

A t the time of Alfred Werner s birth, the only lanthanide elements that had been identified positively were lanthanum and cerium. Yttrium, a lanthanide element by all criteria except electronic configuration, was known also. However, in 1891 when Werner proposed the substance of the coordination theory, all of the elements of the lanthanide series except promethium, europium, and lutetium had been clearly identified and quite well characterized. Only promethium remained undiscovered at the time of Werner s demise. 

The formation and properties of the lanthanide complex species can be best understood by summarizing first some of the pertinent general characteristics of these elements. In their ground states, the lanthanide atoms have the characteristic valence-shell electronic configurations 4/"5 d 6 or 4 / + 6 where n = 0 for lanthanum and 14 for lutetium, overlying the closed-shell xenon arrangement. The atoms are large and readily oxidized. In both aqueous or nonaqueous systems and the solid state, oxidation... 

Following lanthanum are the 14 elements known as the lanthanides, or rare earth series [cerium (Z = 58) to lutetium (Z = 71)]. The rare earth metals have incompletely filled 4f subshells or readily give rise to cations that have incompletely filled 4f subshells. In this series, the added electrons are placed in 4/orbitals. After the 4/subshells are completely filled, the next electron enters the 5d subshell of lutetium. Note that the electron configuration of gadolinium (Z = 64) is [Xt 6s Af 5d rather than [Xe]6 4/ . Like chromium, gadolinium gains extra stability by having half-filled subshells Af). 

The lutetium hahdes (except the fluoride), together with the nitrates, perchlorates, and acetates, are soluble in water. The hydroxide oxide, carbonate, oxalate, and phosphate compotmds are insoluble. Lutetium compounds are all colorless in the solid state and in solution. Due to its closed electronic configuration (4f " ), lutetium has no absorption bands and does not emit radiation. For these reasons it does not have any magnetic or optical importance, see also Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Neodymium Praseodymium Promethium Samarium Terbium Ytterbium. 

Hund 22) described the relations between atomic spectroscopy and the Periodic Table. This was a most important pioneer work but made one uncertain extrapolation the almost invariant trivalency made it highly probable that the groundstate of the neutral atoms from lanthanum to lutetium belong to the electron configuration [Xe] 4fcore electrons. We write [68] for the closed shells [Xe] 4fi which are the ground states of Yb+2, Lu+3, Hf+ , . .. 

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