From: Rabbi Moshe Sofer
To: Rabbi Sender Meizlish
A rabbi who traveled to Eretz Yisrael authorized only one-fifth of charity funds collected for him to be given to his abandoned wife, which was insufficient for her needs. The Chasam Sofer initially rejected redirecting the full funds as an alteration of donor intent, but reconsidered and ruled that since the wife cannot be compelled to join her husband in Eretz Yisrael, he remains fully obligated to support her, and giving her adequate maintenance actually fulfills the donors' intent by allowing him to remain there without facing excommunication; the court may also increase the authorized amount since the husband revealed his intent to support her and the specified sum is insufficient.
Source: Shu"t Chasam Sofer EH I §132