Copy file with target name with diacritics

Take a PDF file named `Gomez.pdf` and pass the command `cp Gomez.pdf Gómez.pdf`. Then opening the new `Gómez.pdf` is impossible. It’s apparently corrupted. If you then pass `cp Gómez.pdf Gamez.pdf` the file `Gamez.pdf` can be opened again. I work heavily with diacritics because I have many PDF files with student names (mostly Spanish names). Thanks in advance for your help. Please, tell me if I can help debugging.