In a molecule, according to the book, when bonds exists, they vibrates
and there are three typrs of vibrations --- scissoring, asymmetrical stretch and symmetrical stretch
But, as far as I know, there are also something called strain --- angle strain, torsional strain and steric strain.
I want to ask whether they are the same or some relevant concepts?
2. infrared spectroscopy
I want to know the principal and operation procedures, in detail, of the infrared spectrophtometer in mearsuring the transmittance of infrared radiation.
It is not mentioned in notes/books.
typo correction & amendment for Q1 ... and there are FOUR TYPES of vibrations --- scissoring, twisting, asymmetrical stretching and symmetrical stretching ...
Thx, but some questions about IR spectroscopy also raised.
For each molecule, there is fingerprint region, which is at 400~500cm-1 and is unique to any molecule But in your answer, it said the anhydrous salt plates used for treating liquid absorb IR of less than 650cm-1; or for solid, nujol may be used which have major peaks at 1370 and 1450cm-1
So, wouldn't the fingerprint region be distracted? Besides, from wikipedia, the fingerprint region actually are most single bonds vibrations (e.g. C-C and C-H) Does that means the transmittance of IR at that range reflects the existence of certain single bonds?
If yes, wouldn't the molecules of structural isomers(e.g. propan-1-ol and propan-2-ol) have same fingerprint region as they have same number of C-H, C-C and C-O bonds?