Knowledge Bank

The wavelength-resolved fluorescence excitation technique has been used to record the (0,0) band of the $b3\Pi 1-X1\Sigma +$ electronic transition of HfO at a resolution of $0.03cm-1$. $Previously1$, this transition has been assigned as a $B1\Pi -X1\Sigma +$ electronic transition. The principal constants (in $cm-1$) obtained from recent and previous $analyses1,2$ are: $StateConfigurationT0B0[31.4]3\Phi 45d6pz+22655.820.3719[31.4]3\Phi 35d6p31392.170.3699[31.4]3\Phi 15d6p29208.320.3696G1\Sigma +5g6s30032.706(8)0.369070(3)F1\Sigma +(3\Pi 0+)6s69(?)27351.136(8)0.364688(3)E1\Pi (c3\Sigma 1+)5d6s25176.878(7)0.367694(3)e0.368294(4)fD1\Pi 5d6s23503.280(5)0.368191(3)e0.367460(3)fX1\Sigma +6220.00.38564405(2)a3\Delta 35d6sz0.378644(7)a3\Delta 25d6s10152.303(12)0.377957(13)a3\Delta 15d6s9525.377(9)0.377284(9)b3\Pi 25d6sz+7928.8780.377841(7)b3\Pi 15d6s17528.168(7)0.377105(9)e0.376591(9)fb3\Pi 05d6s16882.564(9)0.377188(9)b3\Pi 0+5d6s16586.955(9)0.377080(9)$ Ligand field theory (LFT) calculations were used to suggest electronic configurations for the excited states of HfO. New electronic assignments based on LFT predictions for the F and E states are indicated in parentheses. Work supported by AFOSR under grants F19628-90-C-025 and F49620-92-J-0215.