Bruker Elexsys-II E500 CW system comprises:

• X-band (9.3 GHz) bridge
• Q-band (35 GHz) bridge
• ENDOR (X-band CW)
• Liquid helium flow cryostats for low temperature measurements at X- and Q-bands, and ENDOR.

Technical specification:

X-Band CW EPR

• Working frequency range: 9.2 – 9.9 GHz;
• Output microwave power in levelled mode: 200 mW;
• Super-High Sensitivity CW-EPR Resonator
• Unloaded Q-factor: > 16 000;
• Max modulation amplitude: 20 G;
• Window for optical access;
• Weak Pitch signal-to-noise ratio: 3000 : 1;
• Absolute sensitivity: 1.0 x 10⁹ spins / 1 G line width;
• Low temperature measurements: 3.8 – 298 K operated with liquid helium flow cryostat
• Measurements at 77 K with liquid nitrogen finger dewars
• Automated goniometer for angular dependency measurements of single crystals

Q-Band CW EPR

• Working frequency range: 33.85 – 34.15 GHz;
• Max output microwave power: 80 mW;
• Max sample access: Æ3 mm;
• Max modulation amplitude: 20 G (100 KHz);
• Weak Pitch signal-to-noise ratio: 2000 : 1;
• Absolute sensitivity: 1 x 10⁹ spins / 1 G line width;
• Low temperature measurements: 3.8 – 298 K operated with liquid helium flow crysostat. For Q-band measurements whole cavity is cooled.

Magnetic field Specs

• Operating range: -1 … +17 kG
• Integrated rapid scan coils;
• Impedance 3 Ω, water cooled;
• Rapid scan
• Magnetic field ramp range: up to 200 G;
• Scan rate: up to 200 Hz;

X-BAND CW ENDOR Unit DICE-II CW ENDOR/TRIPLE System

• X-Band CW
• Frequency modulation with up 100 kHz rate and
• up to 5 MHz amplitude
• Amplitude modulation with 50 % duty cycle
• ENDOR Induced EPR (EIE)
• 2D ENDOR vs. Magnetic Field