Millimeter- and submillimeter-wave spectrum and molecular constants of cuprous chloride

Monomeric cuprous chloride (CuCl) has been produced an an intermediate reaction product of copper and chlorine gas at 1000°K. Rotational transitions of 63Cu35Cl, 65Cu35Cl, 63Cu37Cl, and 65Cu37Cl have been measured in the millimeter and submillimeter wave region. Transitions have been observed in 7 different vibrational states and for J as high as 32→33. Analysis of the data yields the following Dunham and equilibrium coefficients for 63Cu35Cl: Y01 = 5343.72266(100) MHz, Y11 = −30.37285(120) MHz, Y21 = 0.06021(46) MHz, Y31 = −0.061(50) kHz, Y02 = −3.89432(77) kHz, Y12 = 0.00234(47) kHz, Y03 = −0.0006220(10) Hz, Be = 5343.768(20) MHz, ωe = 417.599(42) cm−1, ωexe = 1.617(6) cm−1; for 65Cu35Cl: Y01 = 5284.98184(100) MHz, Y11 = −29.87340(120) MHz, Y21 = 0.05889(46) MHz, Y31 = −0.059(50) kHz, Y02 = −3.80917(77) kHz, Y12 = 0.00227(47) kHz, Y03 = −0.0006017(10) Hz, Be = 5285.026(20) MHz, ωe = 415.297(42) cm−1, ωexe = 1.599(6) cm−1; for 63Cu37Cl: Y01 = 5158.15294(100) MHz, Y11 = −28.80453(120) MHz, Y21 = 0.05610(46) MHz, Y31 = −0.056(50) kHz, Y02 = −3.62854(77) kHz, Y12 = 0.00214(47) kHz, Y03 = −0.0005594(10) Hz, Be = 5158.195(20) MHz, ωe = 410.284(42) cm−1, ωexe = 1.561(6) cm−1; for 65Cu37Cl: Y01 = 5099.41148(110) MHz, Y11 = −28.31388(120) MHz, Y21 = 0.05483(46) MHz, Y31 = −0.054(50) kHz, Y02 = −3.54636(77) kHz, Y12 = 0.00208(47) kHz, Y03 = −0.0005405(10) Hz, Be = 5099.453(20) MHz, ωe = 407.941(42) cm−1. ωexe = 1.543(6) cm−1. The Dunham potential constants for cuprous chloride are a0 = 244588.0(480) cm−1, a1 = −3.21936(32), a2 = 6.908(26), a3 = −11.68(23), and the equilibrium internuclear distance is re = 2.051177(8) Å.