I am a bit confused about the correct name of $\mathrm{LaMnO}_3$. Is it lanthanium manganate or lanthanum manganite?
I was assuming that since $\mathrm{SrTiO}_3$ is called strontium titanate, $\mathrm{LaMnO}_3$ would then be called lanthanium manganate, but I got confused when I heard a collegue referring to it as manganite and after reading a wikiepdia article on $\mathrm{La}_x\mathrm{Sr}_{1-x}\mathrm{MnO}_3$ where they also used the term manganite.
Which is the correct form, or are they simply interchangeable?
Answer
Let's go down the ladder. $\ce{KMnO4}$ is permanganate, Mn(VII). $\ce{K2MnO4}$ is manganate, Mn(VI). $\ce{K4MnO4}$ is manganite, Mn(IV). $\ce{LaMnO3}$ is called both manganate and manganite, but Mn(III). In a proper world it should be lower than that manganite. They are pedagogically both wrong if it is La(III).
http://dictionary.sensagent.com/potassium%20manganite/en-en/
Manganese oxidation state nomenclature is a real world mess. Drawing nomenclature parallels to Cl(VII) and downward is not valid. Drawing nomenclature parallels to titanium is poor, for Ti(IV) is the highest common oxidation state. $\ce{SrO + TiO2}$ gives $\ce{SrTiO3}$, properly called titanate, for it is Ti(IV) on both sides.
Organic had the same problem. The highest valence carbocation was tricoordinate, hence a carbonium ion. Magic Acid gave $\ce{CH5^+}$. Carbonium ions were renamed carbenium ions to general confusion. Then, $\ce{CH6^{2+}}$. Organic dropped the ball with direction of optical rotation versus geometric left and right. It was flat out stupid designating E ("trans") and Z ("cis") olefins. The designation should have been abstract rather than language-originated.
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