The solid state crystal data of a mer isomer of the [Mn(CF3COCHCOC4H3S)3] complex, [Mn(tfth)3], exhibits
elongation Jahn-Teller distortion (elongation of the metal-ligand bonds along the z-axis and shortening
of the metal-ligand bonds along both the x and y-axes). Density functional theory calculations (DFT)
show that one fac and three mer isomers of [Mn(tfth)3] can exist. The difference between the three mer
isomers of [Mn(tfth)3] is that the Jahn-Teller elongation of the two trans axial Mn-O bonds along the zaxis
occur along three different Otfth-Mn-Otfth bonds. DFT calculations further show that the ground state
geometry of all the [Mn(tfth)3] isomers exhibits elongation Jahn-Teller distortion.