Tweeted twitter.com/StackChemistry/status/844653311445880832 occurred Mar 22 '17 at 20:53 4 mathjax for rotational constants edited Mar 19 '17 at 4:36 pentavalentcarbon 6,25344 gold badges3838 silver badges6565 bronze badges I have been trying to calculate the rotational constants (B$$B$$) for $$\ce{CO}$$ and $$\ce{CO2}$$ from IR Vibrational-Rotational spectra. I know that for $$\ce{CO}$$ the peak spacing is approximately 2B $$2B$$ (ignoring effects due to centrifugal distortion) however for $$\ce{CO2}$$ it seems the peak spacing represents 4B$$4B$$ instead when I compare my results to literature? Does anybody have any explanation as to why this is, or could provide reading on this subject to explain why the peak spacing for $$\ce{CO2}$$ is 4B$$4B$$? I have been trying to calculate the rotational constants (B) for $$\ce{CO}$$ and $$\ce{CO2}$$ from IR Vibrational-Rotational spectra. I know that for $$\ce{CO}$$ the peak spacing is approximately 2B (ignoring effects due to centrifugal distortion) however for $$\ce{CO2}$$ it seems the peak spacing represents 4B instead when I compare my results to literature? Does anybody have any explanation as to why this is, or could provide reading on this subject to explain why the peak spacing for $$\ce{CO2}$$ is 4B? I have been trying to calculate the rotational constants ($$B$$) for $$\ce{CO}$$ and $$\ce{CO2}$$ from IR Vibrational-Rotational spectra. I know that for $$\ce{CO}$$ the peak spacing is approximately $$2B$$ (ignoring effects due to centrifugal distortion) however for $$\ce{CO2}$$ it seems the peak spacing represents $$4B$$ instead when I compare my results to literature? Does anybody have any explanation as to why this is, or could provide reading on this subject to explain why the peak spacing for $$\ce{CO2}$$ is $$4B$$? 3 edited tags; edited tags | link edited Mar 18 '17 at 14:13 orthocresol♦ 43.4k77 gold badges136136 silver badges267267 bronze badges 2 deleted 8 characters in body edited Mar 18 '17 at 5:20 ringo 20.6k66 gold badges6363 silver badges117117 bronze badges I have been trying to calculate the rotational constants (B) for CO$$\ce{CO}$$ and CO2$$\ce{CO2}$$ from IR Vibrational-Rotational spectra. I know that for CO$$\ce{CO}$$ the peak spacing is approximately 2B (ignoring effects due to centrifugal distortion) however for CO2$$\ce{CO2}$$ it seems the peak spacing represents 4B instead when I compare my results to literature? Does anybody have any explanation as to why this is, or could provide reading on this subject to explain why the peak spacing for CO2$$\ce{CO2}$$ is 4B? Thanks! I have been trying to calculate the rotational constants (B) for CO and CO2 from IR Vibrational-Rotational spectra. I know that for CO the peak spacing is approximately 2B (ignoring effects due to centrifugal distortion) however for CO2 it seems the peak spacing represents 4B instead when I compare my results to literature? Does anybody have any explanation as to why this is, or could provide reading on this subject to explain why the peak spacing for CO2 is 4B? Thanks! I have been trying to calculate the rotational constants (B) for $$\ce{CO}$$ and $$\ce{CO2}$$ from IR Vibrational-Rotational spectra. I know that for $$\ce{CO}$$ the peak spacing is approximately 2B (ignoring effects due to centrifugal distortion) however for $$\ce{CO2}$$ it seems the peak spacing represents 4B instead when I compare my results to literature? Does anybody have any explanation as to why this is, or could provide reading on this subject to explain why the peak spacing for $$\ce{CO2}$$ is 4B? 1 asked Mar 18 '17 at 5:01 Brandon Lowe 1622 bronze badges