Preparation and spectroscopic characterization of two HoCl3-galactitol complexes and one ErCl3-galactitol complex

► The coordination between metal ion and carbohydrates are important. ► Two HoCl3, one ErCl3-galactitol complex were prepared. ► Structures of HoG(I) and ErG were deduced from IR, FIR, THz, TGA and ESI-MS spectra. ► The X-ray crystal structure of HoG(II) was determined.