//JPL		p-NH3-hfs
//Temp (K)	log(Z)
2.291	1.4618
5.000	1.5099
9.375	1.5412
18.75	1.6465
37.50	1.8693
75.00	2.1800
150.0	2.5581
225.0	2.7990
300.0	2.9781
500.0	3.3203
1000.0	3.8355		