Temperature-independent paramagnetic

The two primary causes of shielding by electrons are diamagnetism and temperature-independent paramagnetism (TIP). Diamagnetism arises from the slight unpairing of electron orbits under the influence of the magnetic field. This always occurs so as to oppose the field and was first analysed by Lamb [7]. A simplified version of his fomuila. 

Our new measurements within the temperature range 4.2 to 300 K shows that Pu(C0T)2 is temperature independent paramagnetic, Fig. 5. A small paramagnetic impurity was found which corresponded to Vgff = 0.01 y. Extrapolation for l/T- 0 yielded Xjip = (191 10) x 10-6 emu. The diamagnetic correction used, =... 

Within the general trend in the behavior across the actinide series, their alloys, and their metallic compounds from superconductors to local moment magnets, the only serious irregularity occurs in some plutonium compounds. These compounds should be magnetic but turn out to be temperature independent paramagnets. 

In contrast to chloride compounds, niobium oxides have a VEC of 14 electrons, due to an overall anti-bonding character of the a2u state, caused by a stronger Nb-O anti-bonding contribution. In some cases, the VEC cannot be determined unambiguously due to the uncertainty in the electron distribution between the clusters and additional niobium atoms present in the majority of the structures. The 14-electron compounds exhibit semiconducting properties and weak temperature-independent paramagnetism. Unlike niobium chlorides, the oxides do not exhibit a correlation between the electronic configuration and intra-cluster bond distances. 

Two other actinyl ions, UO (5/°) and NpO (5/ ), are worth mentioning here. Although the uranyl ion contains no unpaired/electrons, its complexes may display a weak temperature-independent paramagnetism because of... 

Ramsey obtained ay, by first-order and op by second-order perturbation theory (76) variational treatments give similar results (14, 71, 73). The term wp is sometimes called the second-order paramagnetic term and sometimes the high-frequency term (14), because of the dependence of the (temperature-independent) paramagnetism in molecules on the high-frequency matrix elements of the orbital moments (91). 

The symbol TIP means that the compound has an almost temperature independent paramagnetism. 

K2ZrF5 has been mentioned by Ehrlich.31 It is described as a white solid which can be sublimed and which exhibits slight temperature-independent paramagnetism. 

In these clusters the metal has a formal oxidation state of 2.5, with 10 electrons available for M—M bonding in the Nb4 group the compounds are diamagnetic with a slight temperature independent paramagnetism. It is noticeable that Nb(l) and Nb(2) have different arrangements, which led to the proposal of different formal oxidation states +11 for Nb(l) and +III for Nb(2). 

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