• Electron spin resonance spectroscopy
  • Mössbauer spectrometer

Electronic Magnetic Resonance Spectroscopy (ESR)
A Bruker model ESP 300 Spectrometer is available in the Magnetic Resonance Laboratory of the Bariloche Atomic Center. This equipment allows the measurement of the electronic resonance spectrum of a spin system (ESR), which corresponds to the absorption of energy of the incident microwave field when the microwave radiation frequency is tuned to the natural frequency of the system. In diluted paramagnetic materials, the ESR spectrum provides information on the nature of the resonant species, the symmetry of the crystalline environment, and also allows the resonant ions to be quantified. When the system is concentrated, information is also obtained on the nature of the interactions between the magnetic ions. In the case of magnetically ordered compounds, the ferromagnetic resonance spectrum (FMR) allows us to know the magnetic anisotropies and the magnetic couplings present. Carrying out temperature studies can characterize the phase transitions of the system. The Bruker ESP 300 spectrometer has the following characteristics:
It can operate on four different frequencies: 1.2, 9.4, 24 and 35 GHz.
It has an electromagnet that allows the magnetic field to be varied between 0 and 2.1 T.
It is possible to carry out measurements depending on temperature from 4 to 1000 K, depending on the frequency.
Solid samples, powders, thin films, liquids, etc. can be measured.
It has a detection limit of about 1013 spins / Oe

The laboratory also has a new Electronic Paramagnetic Resonance Spectrometer (EPR), a Bruker ELEXSYS II-E500. This state-of-the-art equipment complements the laboratory’s experimental facilities since it has the highest sensitivity within the CW-EPR spectrometers and allows detecting concentrations lower than the picomoles (10-9 moles) of magnetic species.

Alejandro Butera
Elin Winkler

Roberto Zysler
Carlos Ramos

Mössbauer spectrometer
Mössbauer spectroscopy is a local atomic characterization technique based on the Mössbauer Effect that allows studying the properties of materials through Hyperfine Interactions. Because it is a very sensitive technique to changes in the surroundings of the nucleus, it allows us to obtain information on the structure of a crystal, the magnetic ordering, etc. Furthermore, these properties will depend on external conditions such as temperature, pressure and magnetic field.