The Piano Sonata in A minor D 537 of Franz Schubert is a sonata for solo piano, composed in March 1817.
I. Allegro ma non troppo
A minor. The exposition modulates to the submediant, F major, rather than to the usual mediant, C major. The recapitulation begins in the subdominant, D minor, and most of the recapitulation's second group is in A major before a short coda returns to the minor mode for the movement's ending.
II. Allegretto quasi andantino
E major. A five-part rondo with an unconventional key scheme as follows:
A (E major) → B (C major) → A (F major) → C (D minor) → A (E major)
Schubert also composes brief transitions at the ends of each episode--that between the B section and the medial A section features a small amount of the B section's material in F major (the medial A section's key), while that between the C section and the final A section modulates from the C section's D minor up a tone to E minor, and then sits on its dominant for a few measures before the return to the movement's tonic key with the final A section. The movement ends with a short coda that is completely diatonic.
III. Allegro vivace
A minor. In sonata form without development (the exposition modulates to E major, and the recapitulation then begins in E minor and moves to A major).
Ends in the parallel major
The work takes approximately 20 minutes to perform. Daniel Coren has summarised the nature of the recapitulation in the last movement of this sonata. Harald Krebs has noted that Schubert reworked the opening of the second movement of the D. 537 sonata into the opening theme of the finale of the A major piano sonata, D. 959.
References in Popular Culture
The piano sonata is featured in the 1985 film adaptation of E.M. Forster's "A Room with a View," as protagonist Lucy Honeychurch is practicing piano.