Full set of Notes with Fill-Ins - San Jose State University

Chem 155 Unit 6 Page 132 of 316High Resolution and Echelle MonochromatorsAtomic spectroscopy demands high resolutionbecause atomic absorption / emission lines are:1. narrow 2.So we want effective bandwidth Δλ EFF =wD -1 = w d cos(r) / nF to be:We also want resolution (R = λ / Δλ = nN)to be:smalllargeΔλ EFFRw should be small -d should be small smallF should be large largen should be large largeBut there are limitations to the above:If w is too small 1 – no light 2 – exceedsw the ability to focus lightdFLimitations in the fabrication of gratingsHow big of a spectrometer is tolerable?What about n?n is the key…Page 132 of 316