HE-SGM

HE-SGM for NEXAFS/XPS spectroscopy

The HE-SGM beamline is a dipole beamline optimized for NEXAFS spectroscopy in the VUV range. It is designed to cover the light element (C, N, O and F) K-edges which contain important spectroscopic information about soft matter samples, carbon (nano) materials and molecules adsorbed on catalytically relevant surfaces. The beamline monochromator allows for fast scanning over the energy ranges of interest (100 eV - 800 eV). There are a number of similar beamlines at other synchrotron facilities worldwide. With regard to the spectroscopic parameters, the HE-SGM beamline is considered to be in the top three of comparable dipole beamlines. The optical elements of the beamline (mirror, monochromator) were addittionally cleaned with oxygen plasma to remove carbon contamination from their surfaces resulting in crucial decrease of parasitic contributions to the experimental data (Fig. 3). Such uniqueness allows to acquire proper experimental data for organic moleculas thin films with a thickness down to 0.1 monolayer. During reinstallation of the beamline, the adjustment of the entrance slit was improved resulting in a better polarization factor - which increased to 91%.

Responsible scientist, Dr. Alexei Nefedov

Responsible scientist, Dr. Alexei Nefedov

Fig.1 HE-SGM Beamline

Fig.1 HE-SGM Beamline

Fig.2 Optical lay-out and measured performance data

Fig.2 Optical lay-out and measured performance data

Fig.3 Dependence of the direct beam intensity on the photon energy  (transmission function) around C K-edge

Fig.3 Dependence of the direct beam intensity on the photon energy (transmission function) around C K-edge

Properties of the beamline

Properties of the beamline

List of publications
Beamline data
Segment L02
Location (Pillar) 4.1
Source D21 (Dipole)
Monochromator HE-SGM
Energy range 100 - 700 eV
Energy resolution 500-2500
Flux 5e11 photos/(s•100mA)
Polarisation horizontal
Divergence horizontal 1.5 mrad
Divergence vertical 1.5 mrad
Focus size (hor. x vert.) 1.2×0.5 square mm
Fixed endstation HE SGM Station
Flexible endstation(s) no
User endstation not possible
Distance Focus/last valve 500 mm
Height Focus/floor level 1400 mm
Beam availability 24h/d
Phone --