ERRATUM: "A NEW NETWORK FOR HIGHER-TEMPERATURE GAS-PHASE CHEMISTRY. I. A PRELIMINARY STUDY OF ACCRETION DISKS IN ACTIVE GALACTIC NUCLEI" (2010, ApJ, 721, 1570)

We found errors of an order of magnitude in the activation energy barriers of the rate coefficients of some of the important reactions in our high-temperature network. When these errors are corrected, the chemistry behaves differently from the published results under certain conditions. In addition, we decided to use different rate coefficients for two reactions below:

$$\begin{equation} {\rm HNC + H \longrightarrow HCN + H} \end{equation} \tag{ 1 }$$

with the new rate coefficient k = 1.00 × 10⁻¹⁰exp (− 2000/T) cm³ s⁻¹, and

$$\begin{equation} {\rm HNC + O \longrightarrow CO + NH} \end{equation} \tag{ 2 }$$

with k = 7.64 × 10⁻¹²exp (− 1125/T) cm³ s⁻¹. In the previous network, the rate coefficients used were taken from the estimate of Schilke et al. (1992), but for HNC+H we decided to use a value estimated for the temperature region 200 K–1000 K based on the quantum chemical results of Talbi et al. (1996), while for HNC+O we used a high-temperature result by Lin et al. (1992). The estimate for the rate coefficient of H+HNC is in reasonable agreement with that of Sumathi & Nguyen (1998) at 300 K. The new version of the gas-phase chemical network in KIDA (KInetics Database for Astrochemistry),⁵ kida.uva.2012, will contain the high-temperature reactions, including the two in this paper, and the corrected rate coefficients will also be available there.

As a consequence of our error, the calculated abundances are different from those shown in Figures 1–4 in the published version of this article. The corrected abundances are shown in Figure 1 along with the previously published results. This figure shows that the chemistry behaves differently for temperatures T ⩾ 500 K while there are no significant differences at temperatures lower than T ⩽ 300 K.

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For most of the species, the results in the tables in Section 4 of Harada et al. (2010) do not change by more than 20%. The largest differences in major species with fractional abundances greater than 10⁻⁸ are a 30% decrease from the ammonia abundance in Table 2 and a 30% decrease from the acetylene abundance in Table 3, which are still not significant given the order-of-magnitude uncertainties in chemical modeling.