Table B.2: Charge transfer reactions.
Reaction a b Reference

O²⁺ + H $\rightarrow$ O⁺ + H⁺ 7.7E-10 Yan (1997)

C²⁺ + H $\rightarrow$ C⁺ + H⁺ 1.0E-12 Yan (1997)

N²⁺ + H $\rightarrow$ N⁺ + H⁺ 8.6E-10 Yan (1997)

S²⁺ + H $\rightarrow$ S⁺ + H⁺ 1.0E-14 Yan (1997)

Fe²⁺ + H $\rightarrow$ Fe⁺ + H⁺ 1.6E-10 0.17 MHT96

Mg²⁺ + H $\rightarrow$ Mg⁺ + H⁺ 9.0E-14 AR85

Ne²⁺ + H $\rightarrow$ Ne⁺ + H⁺ 1.0E-14 AR85

Si²⁺ + H $\rightarrow$ Si⁺ + H⁺ 1.8E-09 0.28 AR85

O²⁺ + H₂ $\rightarrow$ O⁺ + H₂⁺ 1.0E-09 Yan (1997)

C²⁺ + H₂ $\rightarrow$ C⁺ + H₂⁺ 1.0E-13 Yan (1997)

Fe²⁺ + H₂ $\rightarrow$ Fe⁺ + H₂⁺ 1.0E-14 Yan (1997)

S²⁺ + H₂ $\rightarrow$ S⁺ + H₂⁺ 1.0E-15 Yan (1997)

N²⁺ + H₂ $\rightarrow$ N⁺ + H₂⁺ 3.4E-11 Yan (1997)

N²⁺ + He $\rightarrow$ N⁺ + He⁺ 1.3E-10 Yan (1997)

C²⁺ + He $\rightarrow$ C⁺ + He⁺ 1.0E-10 AR85

O²⁺ + He $\rightarrow$ O⁺ + He⁺ 7.1E-12 0.95 AR85

Ne²⁺ + He $\rightarrow$ Ne⁺ + He⁺ 1.0E-14 BD80

Rate coefficients have the form k = a(T/300)^b and a is in units of cm³ s^-1. MHT96 refers to Maloney et al. (1996). AR85 refers to Arnnaud & Rothenflug (1985). BD80 refers to Butler & Dalgarno (1980).

**Table B.2:** Charge transfer reactions.
Reaction	a	b	Reference
O²⁺ + H $\rightarrow$ O⁺ + H⁺	7.7E-10		Yan (1997)
C²⁺ + H $\rightarrow$ C⁺ + H⁺	1.0E-12		Yan (1997)
N²⁺ + H $\rightarrow$ N⁺ + H⁺	8.6E-10		Yan (1997)
S²⁺ + H $\rightarrow$ S⁺ + H⁺	1.0E-14		Yan (1997)
Fe²⁺ + H $\rightarrow$ Fe⁺ + H⁺	1.6E-10	0.17	MHT96
Mg²⁺ + H $\rightarrow$ Mg⁺ + H⁺	9.0E-14		AR85
Ne²⁺ + H $\rightarrow$ Ne⁺ + H⁺	1.0E-14		AR85
Si²⁺ + H $\rightarrow$ Si⁺ + H⁺	1.8E-09	0.28	AR85
O²⁺ + H₂ $\rightarrow$ O⁺ + H₂⁺	1.0E-09		Yan (1997)
C²⁺ + H₂ $\rightarrow$ C⁺ + H₂⁺	1.0E-13		Yan (1997)
Fe²⁺ + H₂ $\rightarrow$ Fe⁺ + H₂⁺	1.0E-14		Yan (1997)
S²⁺ + H₂ $\rightarrow$ S⁺ + H₂⁺	1.0E-15		Yan (1997)
N²⁺ + H₂ $\rightarrow$ N⁺ + H₂⁺	3.4E-11		Yan (1997)
N²⁺ + He $\rightarrow$ N⁺ + He⁺	1.3E-10		Yan (1997)
C²⁺ + He $\rightarrow$ C⁺ + He⁺	1.0E-10		AR85
O²⁺ + He $\rightarrow$ O⁺ + He⁺	7.1E-12	0.95	AR85
Ne²⁺ + He $\rightarrow$ Ne⁺ + He⁺	1.0E-14		BD80

Source LaTeX | All tables | In the text

	1 Introduction
	2 Model
	3 X-ray induced chemistry
	4 Results and discussion
	5 X-ray tracers
	6 AFGL 2591 models
	7 Calculated emission lines
	8 Conclusion
	References
	Online Material
	Appendix A: Initial chemical abundances
	Appendix B: Electron recombination and charge transfer reactions
	Appendix C: Influence of $T{_{{\rm X}}}$ and $N{_{{\rm H,in}}}$
	Appendix D: Influence of an outer FUV field and cosmic rays
	Appendix E: Comparison to observations