<p class=\"MsoNormal\" style=\"margin-bottom: 0.0001pt; text-align: justify;\"><span style=\"font-size: 10.0pt; font-family: \'Times New Roman\',\'serif\';\">Aluminium is a third group element according to the periodic table. Chemically it is a reactive metal often forming complexes within its binary alloys.In the present work we have dealt with the impact of eigenvalues on the superconducting state parameter viz. the electron-phonon coupling strength of this metal.</span><span style=\"font-size: 10.0pt; font-family: \'Times New Roman\',\'serif\';\">We have also dealt with the same for two binary alloys of it viz. aluminium-magnesium and aluminium-zinc. For this purpose</span><span style=\"font-size: 10.0pt; font-family: \'Times New Roman\',\'serif\';\">we have computed the non-local screened form factor for each of them. Initially the orthogonalised plane wave parameter has been taken as unity.</span><span style=\"font-size: 10.0pt; font-family: \'Times New Roman\',\'serif\';\">Thereafter Vashishta-Singwi form of exchange and correlation are employed. The core energy eigenvalues of Herman-Skillman have been used.</span><span style=\"font-size: 10.0pt; font-family: \'Times New Roman\',\'serif\';\">Our results are quite satisfactory for the metal as well as its present alloys.</span><span style=\"font-size: 10.0pt; font-family: \'Times New Roman\',\'serif\';\">Our computation reveals that the superconducting state parameter can be reasonably reproduced by Harrison&rsquo;s first principle pseudopotential technique along with McMillan&rsquo;s formalism provided a proper choice of the core energy eigenvalues is made.</span></p>
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<p class=\"MsoNormal\" style=\"margin-bottom: .0001pt; text-align: justify;\"><strong><span style=\"font-size: 10.0pt; line-height: 115%; font-family: \'Times New Roman\',\'serif\';\">Key words : </span></strong><em><span style=\"font-size: 10.0pt; line-height: 115%; font-family: \'Times New Roman\',\'serif\';\">Superconducting state parameter, Orthogonalised plane wave parameter, Eigenvalue, Form factor.</span></em></p>