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type decomposition of 1 /r in terms of a pair of short-range (in terms of complimentary error function) and long-range (in terms of error function) contributions; former can be obtained analytically whereas the latter is computed directly from FFT of real-space values. 

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Here ρ ( k$_{g}$ ), the Fourier integral of density, is easily calculated from standard FFT, while v c $_{H}$( k$_{g}$ ) signifies that of Coulomb interaction kernel in the grid which requires caution. The nonlocal XC functionals of [36–38] are used in this work; while for LDA calculations homoge- neous electron-gas correlation [31] is used. The gradient-dependent functionals are handled by using a finite-orbital expansion method [40], which allows one to bypass the calculation of difficult density Hessians. In the end, XC matrix elements are evaluated as, 

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where γ$_{αα}$ = |∇ ρ$_{α}$ | $^{2}$, γ$_{αβ}$ = ∇ ρ$_{α}$ · ∇ ρ$_{β}$ , γ$_{ββ}$ = |∇ ρ$_{β}$ | $^{2}$. The advantage is that f is a function only of local quantities ρ$_{α}$ , ρ$_{β}$ and their gradients. Non-local functionals are implemented using the Density Functional Repository program [41]. There is no direct analytic route to evaluate two-electron matrix elements. Present work uses numerical integration for these in a 3D CCG covering a cubic box. Resulting matrix-eigenvalue problem is solved accurately and efficiently by means of standard LAPACK library package [42]. Self-consistent solutions are obtained by imposing a tolerance of 10 − 6 for energy and eigenvalues whereas 10 − 5 for potential. 

## III. RESULTS AND DISCUSSION 

At first, we show FT97 and PBE results for 8 atoms and 27 molecules in Table I within the pseudopotential framework. Throughout the whole article, molecular geometries are used from those in NIST database [43]. We report non-relativistic ground-state total, kinetic and potential energies for all these species using the effective core potential of [29, 30]. For sake of completeness, our integrated electron density is also given which can sometimes work as a rough indicator of accuracy and quality attained in a given calculation. Several grid parameters were tried to check convergence, as in previous papers [24, 25]. However as 

