Comparison of present effective collision strengths with the results from Ramsbottom et al. (2001) for the dipole-allowed (a) 3 s ²3 p ^{3  4} S ^o _3/2 → 3 s ²3 p ²( ³ P)4 s  ⁴ P _5/2, (b) 3 s ²3 p ^{3  4} S ^o _3/2 → 3 s ²3 p ²( ³ P)3 d  ⁴ P _5/2, (c) 3 s ²3 p ^{3  2} D ^o _3/2 → 3 s ²3 p ²( ³ P)3 d  ² F _5/2, and (d) 3 s ²3 p ^{3  2} P ^o _3/2 → 3 s ²3 p ²( ¹ S)3 d  ² D _5/2 transitions in Cl iii as a function of electron temperature. Solid curve: present 68- LSJ state calculation; dotted curve: 23- LS state calculation of Ramsbottom et al. (2001).