An upper stack for a nuclear magnetic resonance spectrometer apparatus includes a cryostat having one or more chambers for holding samples in a frozen state. A sample loading tube that also allows He delivery extends to the cryostat, and a sample changer mechanism is disposable at least in part proximate to the cryostat for moving specimens from the cryostat to an NMR probe where they can be heated and melted using inductive heating. A sample ejection tube extends from the sample changer mechanism allowing a clear path for heating a sample in an NMR probe using a laser beam.