See snippet below:
<mechanism name="Cambridge ARS-SC model">
<!-- Prerequisite models. -->
<haca>
<reaction id="H_abs" name="H abstraction">
<reactant>H</reactant>
<product>H2</product>
<A>4.2e13<A> /// MISTAKE HERE!!
<n>0.0</n>
<E units="cal">13.0</E>
<Arev>3.9e12</Arev>
<nrev>0.0</nrev>
<Erev units="cal">11.0</Erev>
</reaction>
</haca>
</mechanism>
Parser not picking up the incorrect end tag for <A>.