Session: Physical Chemistry Poster:

A solvated electron precursor (SEP) is “a complex that displaces one or more electrons from its coordinated metal atom to the periphery of its ligands”. The interactions between alkali metals and ammonia create SEPs with one peripheral electron. This outer electron occupies a quasi−spherical superatomic s−type orbital. Tetrahedral Li(NH)₄ and Na(NH₃)₄ SEPs possess one electron around the [M(NH₃)₄]⁺ core, mimicking H−atom. Fascinatingly, outer electrons of SEPs promote to higher angular momentum atomic shaped orbitals by excitation. The proposed superatomic orbital order for one electrons SEPs is 1s, 1p, 1d, 2s, 1f, 2p, 2d. Neutral SEPs with alkali earth metals have two electrons orbiting around the M(NH₃)_n²⁺ skeleton (e.g.: Be(NH₃)₄, Mg(NH₃)_n_=4,5,6, Ca(NH₃)_n_=6,8) resembling He atom. Electronic structures of most of their excited states are heavily multi−reference. However, their cationic species follow similar Aufbau principle as Li(NH)₄ or Na(NH₃)₄. Transition metal based SEPs are remarkable class of molecules and extremely challenging to study. The ground states of Ti(NH₃)₆⁺ and Ti(NH₃)₆ complexes have s¹ and s²electronic configurations respectively and belongs to SEP category.

Superatomic orbitals of Li(NH<sub>3</sub>)<sub>4</sub>

Superatomic orbitals of Li(NH₃)₄

Dr Isuru R Ariyarathna

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