Calculation of rotatlonal-vlbratlonal preionization in H2 by multichannel quantum defect theory

Multichannel quantum defect theory is adapted to treat simultaneous rotational and vibrational preionization in H₂. The strongly preionized spectrum between the N⁺ = 0 and N⁺ = 2 rotational thresholds of photoionization of H 2 X 1 ∑ g + ( J ″ = 0 ,   v ″ = 0 ) https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780203746608/2f2626dc-8555-4899-8d1e-59e7f2e652dc/content/eq3131.tif"/> to produce H 2 + X 2 ∑ g + ( N + , v + = 0 ) https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780203746608/2f2626dc-8555-4899-8d1e-59e7f2e652dc/content/eq3132.tif"/> is computed as example and good agreement is obtained with the photoionization data of Dehmer and Chupka.