The decompositions of the transmission into interfering and non-interfering contributions are displayed in Figure (d) and Figure . This QI map provides a diagramatic visualization of the Q matrix calculated using Equation . The squares along the main diagonal (highlighted with bold lines) represent the noninterfering transmission terms. As these terms are always positive, they will either be red or change gradually to white when decreasing close to zero. The off-diagonal squares illustrate the QI between different MOs. They may either be red, denoting constructive QI, or be blue, denoting destructive QI. The shade of the color indicates the magnitude of the term. White squares indicate that the magnitude of these items are close or equal to zero. In the case of para-substituted benzene constructive QI dominates the contribution to the transmission, while for meta-substituted benzene, the destructive QI cancels exactly with the non-interfering terms. In both cases, the maps are dominated by interactions between the two frontier orbitals, with lesser contributions from all other orbitals. This result reproduces the earlier work of Gunasekaran et al. on this system. The electronic transmission for butane calculated using the ladder C model is shown in Figure . The transmission varies significantly with the change in the dihedral angle. At a dihedral angle of 180 • there are no anti-resonances whereas two anti-resonances are present at ±2.23eV for a dihedral angle of 0 • . When the dihedral angle is increased from 0 • to 49 • , the anti-resonances move closer to the Fermi energy while the transmission decreases and vanish altogether at a dihedral angle of 50 • . With the further increase in the dihedral angle, the transmission increases again and becomes a broad valley.