@Test
public void testAnticipatedIonState_2() throws ClassNotFoundException, CDKException, Exception {

    RDBERule rule = new RDBERule();
    IMolecularFormula formula = MolecularFormulaManipulator.getMajorIsotopeMolecularFormula("NH4", builder);
    Assert.assertEquals(0.0, rule.validate(formula), 0.0001);
}