What is the ruling on an irreversible divorce with a single pronouncement, without observing the 'iddah in the marital home, especially if the husband is in another country and cannot stay with his wife for the duration of the 'iddah?

A man divorcing his wife with a single, absent (unilateral) pronouncement is permissible if she is ritually pure (tahira) and he has not touched her, or if she is pregnant. This constitutes a revocable divorce (talaq raj'i), allowing him to reconcile with her as long as she is within her waiting period (iddah). The husband is obligated to provide housing for his wife who is revocably divorced or pregnant, and she must remain in the marital home until her iddah expires. She may not be expelled unless she commits a clear act of immorality. The husband is not required to reside with her.