Chemical symbols char [number of atom species][symbol length].

def chemical_symbols(self):
        """Chemical symbols char [number of atom species][symbol length]."""
        charr = self.read_value("chemical_symbols")
        symbols = []
        for v in charr:
            s = "".join(c.decode("utf-8") for c in v)
            symbols.append(s.strip())

        return symbols