In Japanese: 動、静、引、弛、凝、解、分、合
I know little about Chinese, but from what I can gather on Google (and from what little I know of Tai Chi), Tai Chi uses different characters that are more technically related. It may well be that there are some close linkages.
It's been a while.
Yes I believe the Tai Chi 掤、履、擠、按、採、列、肘、靠 are more technically related in that these are applications. The 8 energies you mentioned above are interesting in that last two 分 & 合 are similar to the opening and closing of Taichi 開 and 合.
動、静 - movement and stillness - in Chinese arts movement refers to the actual techniques and stillness training usually refers to meditation or zhan zhuang (pole standing).
引 - leading - this is a common concept in Taichi - as in leading into emptiness - apologies but I think pulling is too strong a word
弛 - what you translate as loosening, this character not commonly used in Chinese martial arts but perhaps this is the Japanese way of expressing the concept of "Song" 鬆 or relaxation?
凝 - what you translate as congealing - perhaps the corrollary here is 沉 or "sinking" or being connected using whole body power - just speculating here?
解 - what you translate as melting - I disagree with the translation as this is more unravelling as unravelling a knot, I am having trouble finding an exact match but loosening may perhaps be a better translation here rather than above- perhaps this is sensitivity to escape from joint locks or in wresting. Again a guess.
As for Mark's comment that these are just purely opposites - yes and no, looking at the concepts it seems a little more complicated than that. Sometimes in classical writing the author throws a bunch of opposites for stylistic effect (such as he searched to the right and the left, to the eastern mountain and western sea, to the palaces and the homes of the people, etc.) but this seems to be a bit more than that as each concept should be "unpacked" and is important.
I have to defer to your experience and authority for the Japanese somewhat as I know for a fact that Japanese Kanji do not always have the same meaning as the Chinese Hanzi, especially for modern Japanese. But for such characters, more classical contexts the meaning is usually similar or has an older classical Chinese meaning rather than the modern Chinese meaning.