Block-localized wavefunction method

Alternatively, the height of the crossing point can be calculated with any MO-based method, by determining the energy of the reactant wave function at zero iteration (see Appendix 23A), by constrained optimization of block-localized wavefunctions [44], or by an energy decomposition scheme of the Morokuma-analysis type [45]. Lastly, the height of the crossing point can be computed by means of molecular mechanical methods [46], or related empirical VB calculations [47,48]. 

NBO)-based approaches (iv) aromatic fluctuation index (FLU) by M. Sola and coworkers (v) block-localized wavefunction (BLW) method by P. v. R. Schleyer and Y. Mo and (vi) energy decomposition analysis (EDA) by F. M. Bickelhaupt and coworkers. 

Block localized wavefunction (BLW) method s The electron delocalization to the cationic carbon and neutral boron center can be estimated by removing the vacant p-orbitals from the expansion space of molecular orbitals. Although this simple orbital deletion procedure (ODP) technique is limited to the analysis of positive hyperconjugation in carbocations and boranes, it has been generalized and extended to the block localized wavefunction (BLW) method. ... 

Mo Y, Song L, Lin Y (2007) Block-localized wavefunction (blw) method at the density functional theory (dft) level. J Phys Chem A 111(34) 8291-8301. dol 10.1021/jp0724065... 

The BLW method combines the MO and VB theories. In this method, the wavefunction for a localized (diabatic) state is defined by limiting the expansion of each MO (called block-localized MO) to a predefined subspace. Block-localized MOs belonging to different subspaces are generally non-orthogonal. A conceptual advantage of this method is that the BLWs for diabatic states are optimized self-consistently, and the adiabatic state is a combination of a few (usually two or three) diabatic state wavefunctions. 

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