Translawrencium elements, periodicity

Translational symmetry. 74 Translawrencium elements, periodicity of. 615-617 Transport, dioxygen, 895-910 Triatomic molecules and ions, molecular orbitals in, 175-182... 

Fig. 14.15 Long form of the periodic chart extended to include hypothetical translawrencium elements. Blocks with shaded comers represent synthetic elements (Np and Pu are found in nature in trace quantities only). Blocks with dotted lines represent undiscovered elements. (Modified from Seaborg, G. J. Client. Educ. 1969, 46, 626-634. Reproduced with permission.]...

As for the lanthanide elements, the actinides (actinium to nobelium) are placed as a set of 14 elements in the separate f block, with element 104, lawrencium, being the first member of the fourth transition series. Alternative versions of the Periodic Table have actinium as the first member of the fourth transition series, and have lawrencium as the last of the actinide elements in the series of 14 from thorium to lawrencium. Lawrencium, as does lutetium, possesses a full f set of 14 electrons with a single outer d electron. Some versions of the Periodic Table dodge the above considerations and have 15 lanthanide elements, La-Lu, and 15 actinide elements, Ac-Lr, placed in the Group 3 column. The fourth transition series is unfinished, and the element with the highest Z value which has so far been synthesized is number 112. The names of the translawrencium elements Le. those with atomic numbers greater than 103) were settled in 1997 after many years of international argument. They have now been ratified by the International Union of Pure and Applied Chemistry (lUPAC), and are as shown in Table 3.5. 

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