NMR - magnetic field vs. frequency; Hz vs. T

Can you recalculate Hz to Tesla?

Not really. They are connected, but both have different dimensions, so can't equate them.

1Hz = 1 cycle/second - it is frequency, not magnetic field
Magnetic field strength (B) is measured in Tesla (T).

The larger the magnetic field, the faster the frequency.
1 GHz corresponds to 23.5 T
800 MHz corresponds to 18.8 T

The Earth magnetic field is around 30-60 µT.

Frequencies can be represented also in radians per second (rad/s).

2π rad/s = 1 Hz = 1 s^-1

^{Nucleus frequency depends on the electromagnetic environment: when nearby atoms strip away electrons (like electronegative O or N), then nucleus has higher frequency; so less electrons nearby, stronger the nucleus magnetic field, higher frequency.}
^{frequency of the atom = type of atom x magnetic field strength around the atom}

^{Larmor frequency- precession}

^{The frequency of the precession (Larmor frequency) depends on the gyromagnetic ratio and gyromagnetic ratio units are Hz/T, as:}

^ω=γB

^Where
^{ω is the frequency of the precession}
^{γ is the gyromagnetic ratio}
^{B is the strength of the magnetic field}

^{The precession of the magnetization vector is what we detect in NMR, but because of interference from B0 , the precession can't be measured while the net magnetization is along z-axis. That's why we use radiofrequency pulses to rotate the net magnetization.}

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