Analysis of the atomic structure of colloidal quantum dots of the CdSe family: X-ray spectral diagnostics and computer modelling.

Colloidal quantum dots of the CdSe family have been studied by X-ray absorption near edge structure (XANES) spectroscopy and computer modelling. Cd K edge XANES spectra in colloidal quantum dots based on varisized CdSe nanoparticles have been recorded. Atomic structure of CdSe particles and also CdSe particles doped by transition metal atoms Mn and Co has been modelled based on the density functional theory. The embedding of the doping atoms is shown to result in considerable changes in the local atomic structure of CdSe particles. XANES spectra have been calculated above the Cd K edge in CdSe particles, above the Mn K edge in CdSe:Mn particles, above the Co K edge in CdSe:Co particles. The sensitivity of XANES spectroscopy to small changes in structural parameters of the nanoparticles of CdSe family has been demonstrated that furnishes an opportunity to apply it for the verification of atomic structure parameters around positions of cadmium and doping atoms of transition metals in quantum dots based on CdSe. [ABSTRACT FROM AUTHOR]