import re


def split_coeff(ions):
    """Splits coeffiecients from adduct so it can be processed by molmass
    Parameters
    ----------
    ion : list of strings
    Returns
    -------
    list of lists of strings
        each internal list represents one atom and its multiplier in the adduct
    """
    coeff = []
    all_coeff = []
    for ion in ions:
        if ion[0].isdigit():
            coeff = re.findall('\d+|\D+',ion)
        else:
            coeff = [ion]
        all_coeff.append(coeff)
    return all_coeff