^pof;
Chemistry,;
Faculty;
of;
Science,;
University;
of;
Douala,;
Cameroon;
^pof;
Inorganic;
Chemistry,;
Faculty;
of;
Science,;
University;
of;
Yaounde;
I,;
Yaounde,;
Cameroun;
^pof;
Theoretical;
Chemistry,;
Faculty;
of;
Science,;
University;
of;
Sherbrooke,;
Qudbec;
JI;
K;
2R1,;
Canada;