Compound

Infra-red spectral bands [cm−1]

O-H

C-O

C=N

C-N

M-N

8-HQ

3141 - 3241

1094

1581

1273

-

Cu(II)-8HQ

-

1110

1572

1279

583

Co(II)-8HQ

3227

1106

1576

1281

567

Ni(II)-8HQ

3208

1106

1577

1281

569