Table 4: Values for submillimeter and millimeter emissivity, $Q(\lambda )$, collated from the literature. Estimates are given as $\frac{Q(V)}{Q(\lambda)}$ where the extinction efficiency in the V-band [Q(V)] has been taken, where necessary, to be 1.5 (Whittet 1992). The absorption mass coefficient $\kappa (\lambda )$ is calculated from $Q(\lambda )$ assuming a classical grain radius of $0.1~{\mu}$m and a material density of $\rho =3 \times 10^{3}~$kg m-3. For each measurement the column "Medium'' denotes the type of astrophysical environment where the corresponding grains are believed to be situated.

${\lambda }$		 $\frac{Q(V)}{Q(\lambda)}$ $\kappa (\lambda )$ Medium Reference Comment
($\mu$m)   (cm2 g-1)      
100 760 49 diffuse H I (Milky Way) Bianchi et al. (1999)  
125 2000 19 reflection nebula Hildebrand (1983) $\frac{Q(V)}{Q(\lambda)}$ up to 5000 if $\beta=1$
240 3900 9.7 diffuse H I (Milky Way) Boulanger et al. (1996) DIRBE data; values also given
          at 100 and 140$~\mu$m
250 2500 15 reflection nebula Casey (1991) 5 objects; $\frac{Q(V)}{Q(\lambda)}$ up to 30 000
          depending on the method
250 4400 8.5 diffuse H I (model) Draine & Lee (1984) Uses laboratory data; oscillator
          model for $\lambda>60~\mu$m
400 1900 20 late-type star Sopka (1985)  
736 34 000 1.1 diffuse H I (Milky Way) Boulanger et al. (1996) FIRAS data; values also given
          at 346, 490, 535 and 1100$~\mu$m
850 9100 4.1 cold core Rengarajan (1984)  
850 30 000 1.3 cold core Kramer et al. (2003)  
850 54 000 0.69 diffuse H I James et al. (2002) Using $N_{\rm H}$, metallicity & SCUBA data
850 16 000 2.4 H2 (NGC 891) Alton et al. (2000) RT model of this work & SCUBA data
850 14 000 3.2 H2 (NGC 4013) this work  
850 12 000 2.7 H2 (NGC 5907) this work  
850 25 000 1.5 cold core Bianchi et al. (2003) SCUBA data
1000 18 000 2.1 diffuse H I (model) Mathis & Whiffen (1989)  
1000 180 000 0.22 laboratory (Si crystalline) Agladze et al. (1996); Mean value of both works
        Mennella et al. (1996) (150 000 and 197 000)
1000 40 000 0.95 laboratory (Si amorphous) Agladze et al. (1996); Mean value of both works
        Mennella et al. (1996) (36 100 and 43 600)
1000 1600 24 laboratory (C amorphous) Mennella et al. (1996)  
1200 120 000 0.315 diffuse H I (NGC 4565) Neininger et al. (1996) Authors claim emissivity 2-4
          higher for molecular regions
1200 110 000 0.35 diffuse H I (NGC 5907) Dumke et al. (1997) Outer regions of the galactic disk
1200 110 000 0.34 cold core Bianchi et al. (2003) IRAM data
1200 66 000 0.57 H2 (NGC 4565) this work  


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