I think study of various प्रक्रिया-s and related सूत्र-s involved in obtaining तुमन्त-s should start at the point that the grammatical name of the प्रत्यय is तुुमुँन् but affixes as तुम् because t
- Of तुुमुँन्, the ending न् is इत् by हलन्त्यम् (1'3'3)
- उँ (before न्) is also इत् by उपदेशेऽजनुनासिक इत् (1'3'2)
- These two इत्-s vanish by तस्य लोपः (1'3'9)
- Hence the प्रत्यय affixes only as तुम्
I think the प्रत्यय तुम् qualifies to be आर्धधातुक by आर्धधातुकः शेषः (3'4'114)
It would nevertheless be good to collect तुमन्त-s of different धातु-s and also of different उपधातु-s, such that the collection will bring forth different प्रक्रिया-s involved in obtaining तुमन्त-s
Some धातु-s which come to mind are (1) गम् => गन्तुम्, गामयितुम् (2) नम् => नमितुम् (3) दृश् => द्रष्टुम् (4) कृ => कर्तुम्, कारयितुम् (5) पा => पातुम् (6) दा => दातुम् (7) अस् / भू (Note अस्तेर्भूः 2'4'52) => भवितुम् भावयितुम् (8) जि => जेतुम् (9) ब्रू / वच् => वक्तुम् (Note ब्रुवो वचिः 2'4'53) (9) भिद् => भेत्तुम् (10) भुज् / भुञ्ज् => भोक्तुम्
I had done some such effort across 4 posts on
तुमन्तसिद्धिः as linked here. Those were done 5 years ago in 2013. I guess I should review those posts to edit them for any errors therein and also for improvement of the presentation and for updating based on my study over the last 5 years.
In the instance of study of any topic of Sanskrit grammar, one curiosity always crops up in my mind about what examples one can find in गीता. So, I would like to explore what all तुमन्त-s one would come across in गीता. May be, that itself would become an interesting collection !!
In such study one may come across instances, where a तुमन्त may fit, although it is not used, e.g. नायका मम सैन्यस्य संज्ञार्थं तान् ब्रवीमि ते (1'7) Can there be a तुमन्त in place of संज्ञार्थम् ? If yes, which one would that be ?
I shall be obliged for your response to these thoughts.