TMEM70 forms oligomeric scaffolds within mitochondrial cristae promoting in situ assembly of mammalian ATP synthase proton channel

The infrared spectrum of ammonia has proven to be highly problematic for effective Hamiltonian analysis. The most complete previous study of the 3ν2 and ν4+ν2 bands achieved the accuracy of 0.0069 cm−1 as reflected by the root-mean-square error of their fit, which is slightly more than 10 times the experimental accuracy. In the present study, we performed a global fit of the existing 2141 literature data involving 3ν2, ν4+ν2, 3ν2-ν2, (ν4+ν2)-ν2 together with 1281 new data involving 3ν2-2ν2, 3ν2-3ν2 and (ν4+ν2)-(ν4+ν2) using an effective Hamiltonian together with the Pickett suite of program SPFIT/SPCAT. The new dataset consists of three spectra recorded at the SOLEIL synchrotron facility. The effective Hamiltonian model proposed for 3ν2/ν4+ν2 has achieved experimental accuracy. This success combined with our previous success of the 2ν2/ν4 analysis leads us to believe that the vibrational states higher than 3ν2/ν2+ν4 may be analyzed with effective Hamiltonians as well.