text: The translational partition function equals volume over the cube of the thermal form of this quantity, which is proportional to the square root of beta over molar mass.
full_question: The translational partition function equals volume over the cube of the thermal form of this quantity, which is proportional to the square root of beta over molar mass. In one experiment, this quantity was estimated as one over 0.815 times the square root of the accelerating voltage. For a ground-state particle in a box, this quantity is the twice the length of the box. This quantity for electrons equals twice the lattice (*) spacing, times the sine of the smallest scattering angle, as measured in the Davisson-Germer experiment. This quantity, first hypothesized in a 1924 PhD thesis, is equal to Planck's constant divided by a particle's momentum. For 10 points, name this quantity possessed by all matter according to de Broglie's wave-particle duality, but which for waves, is the distance from crest-to-crest.
first_sentence: The translational partition function equals volume over the cube of the thermal form of this quantity, which is proportional to the square root of beta over molar mass.
raw_answer: de Broglie wavelength [or lambda]