Local density approximations, as with Generalised Gradient Approximations (GGA) are employed extensively by [[solid-state physiscsphysics |solid state physicists]] in ab-initio DFT studies to interpret electronic and magnetic interactions in semiconductor materials including semiconducting oxides and [[Spintronics]]. The importance of these computational studies stems from the system complexities which bring about high sensitivity to synthesis parameters necessitating first-principles based analysis. The prediction of [[Fermi- level]] and band structure in doped semiconducting oxides is often carried out using LDA incorporated into simulation packages such as CASTEP and DMol3 <ref>{{cite journal| last1=Segall| first1=M.D.| last2=Lindan| first2=P.J | title= First-principles simulation: ideas, illustrations and the CASTEP code | journal= Journal of Physics: Condensed Matter | year= 2002| volume=14| issue=11| pages=2717}}</ref>. However an underestimation in [[Band gap]] values often associated with LDA and [[Density_functional_theory#Approximations_.28exchange-correlation_functionals.29|GGA]] approximations may lead to false predictions of impurity mediated conductivity and/or carrier mediated magnetism in such systems. <ref>{{cite journal| last1=Assadi| first1=M.H.N| last2=et al.| title= Theoretical study on copper's energetics and magnetism in TiO<sub>2</sub> polymorphs| journal= Journal of Applied Physics | year=2013| volume=113| issue=23| pages= 233913| url=http://arxiv.org/ftp/arxiv/papers/1304/1304.1854.pdf| doi=10.1063/1.4811539}}</ref>
