Electron Configuration and Magnetic Properties

Electron Configuration and Magnetic Properties 17.5.3.1 Diamagnetism and Paramagnetism 

All the REM elements are paramagnetic as metals, but for their ions the situation is more complex. 

Ion Number of unpaired electrons Magnetic moment. Bohr magnetons pg  

Ln stands for Y, La and Ce-Lu. LniC H ij is an organometallic compound of the metal and cyclopentadienyl ligands C5H5. Values taken from ref [17.12]. 

The ions Y, La + and Lu + are diamagnetic, as are Yb and Ce also. All the other lanthanide ions are paramagnetic. Owing to the shielding of the 4f-electrons from the chemical enviromnent, complexing groups or anions bound to paramagnetic Ian- 

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Use the spectrochemical series to predict the effect of a ligand on the color, electron configuration, and magnetic properties of a d-metal complex (Examples 16.4 and 16.5). 

Table 2. Electron configuration and magnetic properties of the three oxidation states of copper. Cu2+ contains an unpaired electron and is therefore EPR-active. Cu+ and Cu3+ are EPR-inactive. These features are utilized in spectroscopic experiments studying copper oxidation states in electron-transfer reactions. When two Cu2+-centers are in close proximity to each other, antiferromagnetic coupling of the two unpaired electrons renders both copper centers EPR-inactive...

EXAMPLE 8.6 Electron Configurations and Magnetic Properties for Ions... 

Some magnetic properties of the lanthanides are presented in section 3 in comparison with the actinides. Table 33 and fig. 27 should be consulted for specific electronic configurations and magnetic moments in each series. 

Zhang YY, Du SX, Gao H-J (2011) Binding configuration, electronic structure, and magnetic properties of metal phthalocyanines on a Au(l 11) surface studied with ab initio calculations. Phys Rev B 84 125446-125454... 

The lanthanides have electrons in partly filled 4/orbitals. Many lanthanides show colors due to electron transitions involving the 4/orbitals. However, there is a considerable difference between the lanthanides and the 3d transition-metal ions. The 4/ electrons in the lanthanides are well shielded beneath an outer electron configuration, (5.v2 5p6 6s2) and are little influenced by the crystal surroundings. Hence the important optical and magnetic properties attributed to the 4/ electrons on any particular lanthanide ion are rather unvarying and do not depend significantly upon the host structure. Moreover, the energy levels are sharper than those of transition-metal ions and the spectra resemble those of free ions. 

Table 18.1.4. Electronic configuration, ground state term symbol, and magnetic properties of Ln3+ ions...

In the discussion of individual elements we have kept to the traditional order that is, elemental chemistries are considered separately, with reference to their oxidation states. However, it is possible to organize the subject matter from the standpoint of the d" electronic configuration of the metal. This can bring out useful similarities in spectra and magnetic properties in certain cases and has a basis in theory however the differences in chemical properties of d" species due to differences in the nature of the metal, its energy levels, and especially the charge on the ion, often exceed the similarities. Nonetheless, such cross considerations (e.g., in the d6 series V I, Cr°, Mn1, Fe11, Cora, and Nirv) can provide a useful exercise for students. 

An electron s position in an atom or ion can be described by determining its electron configuration and orbital diagram. These representations of an atom or ion can explain physical and chemical properties of the substance, including magnetic attraction. 

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