Slightly and much smaller

Just delete the first verbosity:

Our value of x proved to be slightly smaller for the z potential and much smaller for the y potential than those given in Ref [1].

Also, logic suggests that you need to change either 'value' to 'values' or 'those' to'that'.

Could anyone tell me please when I have a sentence with numerals, like this one:

The parameters were equal for the 7/2^- state at the 6.76- and 11.3-MeV levels, respectively.

Do I have to use a hyphen after the first numeral to imply that there should be a word "level" after it, but it's not included to avoid repetition?

snuppelinaDo I have to use a hyphen after the first numeral to imply that there should be a word "level" after it, but it's not included to avoid repetition?

That is the practice, but overall, it looks a bit messy and confusing. Also, there is no call whatsoever for 'respectively', which requires two sets of matched data.

The parameters were

Yeah, I think this way should be much better, thank you very much!

The hyphen you're asking about is not actually a hyphen, it is a minus (a bit higher than a hyphen) and yes, indicates the state. It is the 7/2minus state that occurs at the levels of 6.76 and 11.3 MeV.

I used "respectively" because initially the sentence is supposed to sound something like this (I forgot to inclu

snuppelinaThe hyphen you're asking about is not actually a hyphen,

Then I suggest you clarify that, too:

The parameters were equal for the negative 7/2 state at the levels of 6.76 and 11.3 MeV. (Or 'negative-7/2'?)

snuppelina "Figures 4 and 5 depict the parameters ... at the levels of 6.76 and 11.3 MeV, respective

Mister MicawberThe parameters were equal for the negative 7/2 state at the levels of 6.76 and 11.3 MeV. (Or 'negative-7/2'?)

Yeah, I did that, thank you!
Just no need to write "negative" because there is a minus sign at the top following 7/2.

snuppelina there is a minus sign at the top following 7/2.

That is what is confusing. I suggest the word instead.

Ok, thank you!