A Selection of Chants,

Vexila Regis, Processional Hymn (Original text)

Salve Crux, Office Hymn for the Feast of the Holy Cross, suggested in the Antiphonal 1949 as suitable for use in Passiontide.

Crux Fidelis, This Hymn provides the basis of the other Office Hymns for Passiontide, Also used in the Good Friday Liturgy. (Original text)

Rex Christe Factor Omnium, Office Hymn from the ancient Roman-French missals.

Other chants can be found here, Passion Sunday