Journal of Physics A Mathematical and GeneralMatrix elements of X xk and e αX x k in the harmonic oscillator basisWłodzisław DuchPublished Dec 21, 1983• 15 citationsPublisherAbstractGeneral and compact formulae for matrix elements of x k and X k X k e αX are derived using the second quantisation technique.DOI10.1088/0305-4470/16/18/024